Staggered synchronization signal blocks in frequency sub-bands for beamformed wireless communications

ABSTRACT

Methods, systems, and devices for wireless communications are described that provide staggered synchronization signal blocks (SSBs) in frequency sub-bands for beamformed wireless communications. Transmissions of SSBs and control channel transmissions (e.g., remaining minimum system information (RMSI) physical downlink control channel (PDCCH) transmissions) may use multiple transmission beams in a beam sweeping procedure. The SSB transmissions may be transmitted using transmission beams that span one frequency sub-band of a number of available frequency sub-bands, and the control channel transmissions may use transmission beams that span two or more of the frequency sub-bands. The SSB beam sweeping procedure may be performed separately during staggered, non-overlapping time periods for each frequency sub-band of the number of frequency sub-bands. Each of the of SSBs may indicate a reference timing of the base station used to identify a set of resources (e.g., a control resource set (CORESET)) that carries control channel transmissions.

CROSS REFERENCE

The present application for patent is a Continuation of U.S. patentapplication Ser. No. 16/777,326 by CHENDAMARAI KANNAN et al, entitled“STAGGERED SYNCHRONIZATION SIGNAL BLOCKS IN FREQUENCY SUB-BANDS FORBEAMFORMED WIRELESS COMMUNICATIONS” filed Jan. 30, 2020, which claimsthe benefit of U.S. Provisional Patent Application No. 62/800,074 byCHENDAMARAI KANNAN et al., entitled “STAGGERED SYNCHRONIZATION SIGNALBLOCKS IN FREQUENCY SUB-BANDS FOR BEAMFORMED WIRELESS COMMUNICATIONS,”filed Feb. 1, 2019, assigned to the assignee hereof, and expresslyincorporated by reference in its entirety.

BACKGROUND

The following relates generally to wireless communications, and morespecifically to staggered synchronization signal blocks (SSBs) infrequency sub-bands for beamformed wireless communications.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal frequency division multiple access (OFDMA), or discreteFourier transform spread orthogonal frequency division multiplexing(DFT-s-OFDM). A wireless multiple-access communications system mayinclude a number of base stations or network access nodes, eachsimultaneously supporting communication for multiple communicationdevices, which may be otherwise known as user equipment (UE).

In some cases, wireless devices (e.g., base stations, UEs, etc.) may usebeamformed or precoded signals for transmission and/or reception ofwireless communications. For example, a base station may utilizebeamformed or precoded transmissions to provide directionaltransmissions that may mitigate path losses that may be experienced bynon-beamformed or non-precoded transmissions which may have a relativelywide beam or omnidirectional transmission pattern. In some cases, a UEmay monitor one or more beams as part of a beam sweeping procedure toidentify a particular beam or beams that are suitable for beamformedcommunications between the UE and the base station. In some cases, theUE may obtain information for communicating with a base station frominformation provided via the beam sweeping procedure. Efficienttechniques for identifying beams and associated information forcommunications may help enhance reliability and efficiency of a networkutilizing beamforming.

SUMMARY

The described techniques relate to improved methods, systems, devices,and apparatuses that support staggered synchronization signal blocks(SSBs) in frequency sub-bands for beamformed wireless communications.Various techniques provide for transmissions of SSBs and control channeltransmissions (e.g., remaining minimum system information (RMSI)physical downlink control channel (PDCCH) transmissions on a particularcontrol resource set (CORESET)) via multiple transmission beams in abeam sweeping procedure. The SSB transmissions, in some cases, may betransmitted using transmission beams that span one frequency sub-band ofa number of available frequency sub-bands, and the control channeltransmissions may be transmitted using transmission beams that span twoor more of the frequency sub-bands. In some cases, the SSB beam sweepingprocedure is performed separately during staggered, non-overlapping timeperiods for each non-overlapping frequency sub-band of the number offrequency sub-bands. In some cases, each of the of SSBs indicates areference timing of the base station that is used to identify a set ofresources that carry the control channel transmissions.

In some cases, a base station transmitting the SSBs and control channeltransmissions may perform a listen-before-talk (LBT) procedure prior totransmitting the SSBs and the control channel transmissions. In somecases, the SSBs may be transmitted in LBT-free transmissions. In caseswhere the SSBs are transmitted after an LBT procedure, an SSB timewindow may be identified, and the SSBs transmitted during the SSB timewindow. In some cases, a number of quantized starting locations areavailable within the SSB time window at which the base station may startthe SSB beam sweeping procedure. In some cases, the SSB beam sweepingprocedure may transmit SSBs on a predetermined sequence of transmissionbeams that starts upon completing the LBT procedure. In other cases, theSSB beam sweeping procedure may transmit SSBs on the predeterminedsequence of transmission beams that starts at a timing boundary withinthe SSB time window.

A method of wireless communications at a user equipment (UE) isdescribed. The method may include monitoring one or more of a set offrequency sub-bands for an SSB from a base station, where each of theset of frequency sub-bands carries a non-overlapping instance of theSSB, receiving a first instance of the SSB via at least a firstfrequency sub-band of the set of frequency sub-bands based on themonitoring, determining a reference timing of the base station based onone or more of information from the first instance of the SSB or afrequency location of the first frequency sub-band relative to areference frequency sub-band of the set of frequency sub-bands,identifying, based on the reference timing, a set of resources for acontrol channel transmission from the base station, where the set ofresources spans two or more of the set of frequency sub-bands, andreceiving the control channel transmission via the set of resources.

An apparatus for wireless communications at a UE is described. Theapparatus may include a processor, memory in electronic communicationwith the processor, and instructions stored in the memory. Theinstructions may be executable by the processor to cause the apparatusto monitor one or more of a set of frequency sub-bands for an SSB from abase station, where each of the set of frequency sub-bands carries anon-overlapping instance of the SSB, receive a first instance of the SSBvia at least a first frequency sub-band of the set of frequencysub-bands based on the monitoring, determine a reference timing of thebase station based on one or more of information from the first instanceof the SSB or a frequency location of the first frequency sub-bandrelative to a reference frequency sub-band of the set of frequencysub-bands, identify, based on the reference timing, a set of resourcesfor a control channel transmission from the base station, where the setof resources spans two or more of the set of frequency sub-bands, andreceive the control channel transmission via the set of resources.

Another apparatus for wireless communications at a UE is described. Theapparatus may include means for monitoring one or more of a set offrequency sub-bands for an SSB from a base station, where each of theset of frequency sub-bands carries a non-overlapping instance of theSSB, receiving a first instance of the SSB via at least a firstfrequency sub-band of the set of frequency sub-bands based on themonitoring, determining a reference timing of the base station based onone or more of information from the first instance of the SSB or afrequency location of the first frequency sub-band relative to areference frequency sub-band of the set of frequency sub-bands,identifying, based on the reference timing, a set of resources for acontrol channel transmission from the base station, where the set ofresources spans two or more of the set of frequency sub-bands, andreceiving the control channel transmission via the set of resources.

A non-transitory computer-readable medium storing code for wirelesscommunications at a UE is described. The code may include instructionsexecutable by a processor to monitor one or more of a set of frequencysub-bands for an SSB from a base station, where each of the set offrequency sub-bands carries a non-overlapping instance of the SSB,receive a first instance of the SSB via at least a first frequencysub-band of the set of frequency sub-bands based on the monitoring,determine a reference timing of the base station based on one or more ofinformation from the first instance of the SSB or a frequency locationof the first frequency sub-band relative to a reference frequencysub-band of the set of frequency sub-bands, identify, based on thereference timing, a set of resources for a control channel transmissionfrom the base station, where the set of resources spans two or more ofthe set of frequency sub-bands, and receive the control channeltransmission via the set of resources.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the monitoring may includeoperations, features, means, or instructions for monitoring two or moreof the set of frequency sub-bands for respective instances of the SSB,and combining two or more instances of the SSB from the monitored two ormore of the set of frequency sub-bands. Some examples of the method,apparatuses, and non-transitory computer-readable medium describedherein may further include operations, features, means, or instructionsfor identifying a fixed time periodicity for monitoring the one or moreof the set of frequency sub-bands for the SSB from the base station. Insome examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, each of the set of frequencysub-bands carries an instance of the SSB that is non-overlapping in timeand non-overlapping in frequency.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying an SSB timewindow for monitoring the one or more of the set of frequency sub-bandsfor the SSB from the base station. In some examples of the method,apparatuses, and non-transitory computer-readable medium describedherein, the SSB may be transmitted using an SSB beam sweeping procedurein which a series of consecutive transmission beams within eachfrequency sub-band each carry a corresponding SSB, and where a sameinitial transmission beam of the series of consecutive transmissionbeams is used irrespective of when the SSB beam sweeping procedurestarts within the SSB time window.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the SSB may be transmittedusing an SSB beam sweeping procedure in which a series of consecutivetransmission beams each carry a corresponding SSB having an SSB indexthat indicates a position of the SSB relative to a frame boundary withineach frequency sub-band of the set of frequency sub-bands. In someexamples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, each instance of the SSBtransmitted via each of the set of frequency sub-bands indicates a sameset of CORESET resources for the control channel transmission from thebase station, and where the control channel transmission is an RMSIPDCCH transmission.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, an SSB payload of eachinstance of the SSB indicates the reference timing of the base stationrelative to the respective instance of the SSB. In some examples of themethod, apparatuses, and non-transitory computer-readable mediumdescribed herein, each frequency sub-band of the set of frequencysub-bands has a corresponding offset from the reference timing of thebase station. Some examples of the method, apparatuses, andnon-transitory computer-readable medium described herein may furtherinclude operations, features, means, or instructions for determining afrequency offset of the set of resources relative to the first frequencysub-band based on information provided by the first instance of the SSB.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the set of resources includesa predetermined starting time resource for the control channeltransmission relative to the reference frequency sub-band of the set offrequency sub-bands. In some examples of the method, apparatuses, andnon-transitory computer-readable medium described herein, the set ofresources includes a control channel time window during which the UE isto monitor for the control channel transmission. In some examples of themethod, apparatuses, and non-transitory computer-readable mediumdescribed herein, a duration of the control channel time window may bebased on an LBT procedure duration and a number of LBT attempts that thebase station is configured to perform before dropping the controlchannel transmission.

A method of wireless communications at a base station is described. Themethod may include identifying a set of frequency sub-bands fortransmitting a set of SSBs via a set of transmission beams in an SSBbeam sweeping procedure, identifying a set of resources for transmittinga set of RMSI control channel transmissions via the set of transmissionbeams in an RMSI beam sweeping procedure, where the set of resourcesspans two or more of the set of frequency sub-bands, transmitting theset of SSBs via the set of transmission beams in the SSB beam sweepingprocedure in each of the set of sub-bands, where the SSB beam sweepingprocedure is performed separately during non-overlapping time periodsfor each frequency sub-band of the set of frequency sub-bands, and whereeach of the set of SSBs indicates a reference timing of the base stationthat is used to identify the set of resources, performing an LBTprocedure for initiating the set of RMSI control channel transmissions,and transmitting, responsive to completing the LBT procedure, the set ofRMSI control channel transmissions via the set of transmission beams inthe RMSI beam sweeping procedure using the set of resources.

An apparatus for wireless communications at a base station is described.The apparatus may include a processor, memory in electroniccommunication with the processor, and instructions stored in the memory.The instructions may be executable by the processor to cause theapparatus to identify a set of frequency sub-bands for transmitting aset of SSBs via a set of transmission beams in an SSB beam sweepingprocedure, identify a set of resources for transmitting a set of RMSIcontrol channel transmissions via the set of transmission beams in anRMSI beam sweeping procedure, where the set of resources spans two ormore of the set of frequency sub-bands, transmit the set of SSBs via theset of transmission beams in the SSB beam sweeping procedure in each ofthe set of sub-bands, where the SSB beam sweeping procedure is performedseparately during non-overlapping time periods for each frequencysub-band of the set of frequency sub-bands, and where each of the set ofSSBs indicates a reference timing of the base station that is used toidentify the set of resources, perform an LBT procedure for initiatingthe set of RMSI control channel transmissions, and transmit, responsiveto completing the LBT procedure, the set of RMSI control channeltransmissions via the set of transmission beams in the RMSI beamsweeping procedure using the set of resources.

Another apparatus for wireless communications at a base station isdescribed. The apparatus may include means for identifying a set offrequency sub-bands for transmitting a set of SSBs via a set oftransmission beams in an SSB beam sweeping procedure, identifying a setof resources for transmitting a set of RMSI control channeltransmissions via the set of transmission beams in an RMSI beam sweepingprocedure, where the set of resources spans two or more of the set offrequency sub-bands, transmitting the set of SSBs via the set oftransmission beams in the SSB beam sweeping procedure in each of the setof sub-bands, where the SSB beam sweeping procedure is performedseparately during non-overlapping time periods for each frequencysub-band of the set of frequency sub-bands, and where each of the set ofSSBs indicates a reference timing of the base station that is used toidentify the set of resources, performing an LBT procedure forinitiating the set of RMSI control channel transmissions, andtransmitting, responsive to completing the LBT procedure, the set ofRMSI control channel transmissions via the set of transmission beams inthe RMSI beam sweeping procedure using the set of resources.

A non-transitory computer-readable medium storing code for wirelesscommunications at a base station is described. The code may includeinstructions executable by a processor to identify a set of frequencysub-bands for transmitting a set of SSBs via a set of transmission beamsin an SSB beam sweeping procedure, identify a set of resources fortransmitting a set of RMSI control channel transmissions via the set oftransmission beams in an RMSI beam sweeping procedure, where the set ofresources spans two or more of the set of frequency sub-bands, transmitthe set of SSBs via the set of transmission beams in the SSB beamsweeping procedure in each of the set of sub-bands, where the SSB beamsweeping procedure is performed separately during non-overlapping timeperiods for each frequency sub-band of the set of frequency sub-bands,and where each of the set of SSBs indicates a reference timing of thebase station that is used to identify the set of resources, perform anLBT procedure for initiating the set of RMSI control channeltransmissions, and transmit, responsive to completing the LBT procedure,the set of RMSI control channel transmissions via the set oftransmission beams in the RMSI beam sweeping procedure using the set ofresources.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, each of the SSBs may betransmitted according to a fixed time periodicity without performing anLBT procedure. Some examples of the method, apparatuses, andnon-transitory computer-readable medium described herein may furtherinclude operations, features, means, or instructions for identifying anSSB time window for each of the set of frequency sub-bands fortransmitting the set of SSBs and performing an LBT procedure during theSSB time window for each of the set of frequency sub-bands prior totransmitting the set of SSBs, where the set of SSBs are transmittedresponsive to successfully completing the LBT procedure.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, a same initial transmissionbeam of the SSB beam sweeping procedure may be used irrespective of whenthe SSB beam sweeping procedure starts within the SSB time window. Insome examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, each of the set of SSBs mayhave an associated SSB index that indicates a position of the SSB withina predetermined SSB pattern relative to a frame boundary within eachfrequency sub-band of the set of frequency sub-bands. In some examplesof the method, apparatuses, and non-transitory computer-readable mediumdescribed herein, each of the SSBs transmitted via each of the set offrequency sub-bands indicates a same set of resources for the RMSIcontrol channel transmissions. In some examples of the method,apparatuses, and non-transitory computer-readable medium describedherein, an SSB payload of each of the SSBs indicates the referencetiming of the base station relative to the respective SSB. In someexamples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, each frequency sub-band ofthe set of frequency sub-bands has a corresponding time offset from thereference timing of the base station. In some examples of the method,apparatuses, and non-transitory computer-readable medium describedherein, each of the set of SSBs provides an indication of a frequencyoffset of the set of resources relative to a respective frequencysub-band of the set of frequency sub-bands used to transmit the SSB.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the set of resources includesa predetermined starting time resource for the RMSI control channeltransmission relative to a reference sub-band of the set of frequencysub-bands. In some examples of the method, apparatuses, andnon-transitory computer-readable medium described herein, the set ofresources may be associated with an RMSI time window during which theRMSI beam sweeping procedure is to be performed, and where a startingtime of the RMSI beam sweeping procedure within the RMSI time window isdependent upon a time of completion of the LBT procedure for initiatingthe set of RMSI control channel transmissions. In some examples of themethod, apparatuses, and non-transitory computer-readable mediumdescribed herein, a duration of the RMSI time window is based on aduration of the LBT procedure and a number of LBT attempts that the basestation is configured to perform before dropping the set of RMSI controlchannel transmissions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a wireless communications system thatsupports staggered synchronization signal blocks (SSBs) in frequencysub-bands for beamformed wireless communications in accordance withaspects of the present disclosure.

FIG. 2 illustrates an example of a portion of a wireless communicationssystem that supports staggered SSBs in frequency sub-bands forbeamformed wireless communications in accordance with aspects of thepresent disclosure.

FIG. 3 illustrates an example of an SSB and RMSI resource configurationthat supports staggered SSBs in frequency sub-bands for beamformedwireless communications in accordance with aspects of the presentdisclosure.

FIG. 4 illustrates another example of an SSB and RMSI resourceconfiguration that supports staggered SSBs in frequency sub-bands forbeamformed wireless communications in accordance with aspects of thepresent disclosure.

FIG. 5 illustrates examples of floating resource configurations thatsupport staggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure.

FIG. 6 illustrates an example of a process flow that supports staggeredSSBs in frequency sub-bands for beamformed wireless communications inaccordance with aspects of the present disclosure.

FIGS. 7 and 8 show block diagrams of devices that support staggered SSBsin frequency sub-bands for beamformed wireless communications inaccordance with aspects of the present disclosure.

FIG. 9 shows a block diagram of a communications manager that supportsstaggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure.

FIG. 10 shows a diagram of a system including a device that supportsstaggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure.

FIGS. 11 and 12 show block diagrams of devices that support staggeredSSBs in frequency sub-bands for beamformed wireless communications inaccordance with aspects of the present disclosure.

FIG. 13 shows a block diagram of a communications manager that supportsstaggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure.

FIG. 14 shows a diagram of a system including a device that supportsstaggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure.

FIGS. 15 through 19 show flowcharts illustrating methods that supportstaggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

Aspects of the present disclosure relate to methods, systems, devices,and apparatuses that support initial access in beamformed communicationsbetween a user equipment (UE) and a base station. In some cases, a basestation may transmit information for initiating an initial accessprocedure using beamformed communications in one or more beam sweepingprocedures. In some cases, a first beam sweeping procedure may provide adiscovery reference signal (DRS) (e.g., a synchronization signal block(SSB) having a primary synchronization signals (PSS), secondarysynchronization signal (SSS), and physical broadcast channel (PBCH) withinitial system information) via a set of beams transmitted using afrequency sub-band of a number of available frequency sub-bands. SSBtransmissions, in some cases, may be transmitted using transmissionbeams that span one frequency sub-band of a number of availablefrequency sub-bands. In some cases, the first beam sweeping proceduremay be performed separately during staggered, non-overlapping timeperiods for each frequency sub-band of the number of frequencysub-bands. In some cases, each of a number of SSBs transmitted in thebeam sweeping procedure in each sub-band indicates a reference timing ofthe base station that is used to identify a set of resources (e.g., acontrol resource set (CORESET)) that carry control channel transmissions(e.g., remaining minimum system information (RMSI) physical downlinkcontrol channel (PDCCH) transmissions). In some cases, the controlchannel transmissions may provide a location of resources for a sharedchannel transmission of system information (e.g., an RMSI physicaldownlink shared channel (PDSCH) transmission that provides systeminformation parameters).

A second beam sweeping procedure may provide the control channeltransmissions (e.g., RMSI PDCCH transmissions in a CORESET indicated bythe SSB) via the set of beams used in the first beam sweeping procedure,and that may be transmitted using multiple frequency sub-bands. In somecases, a listen-before-talk (LBT) procedure may be performed before oneor both of the beam sweeping procedures, and transmissions initiatedonly when the LBT procedure indicates the one or more frequency bandsare not occupied by other transmitters. In cases where an LBT procedureis used before the first beam sweeping procedure, a sequence oftransmission beams may be established relative to when the LBT procedureis completed or relative to a timing boundary. A UE may monitor fortransmissions of the first beam sweeping procedure and, based on theDRS, determine the CORESET resources to monitor for the control channeltransmission (e.g., the RMSI PDCCH transmission). In some cases, theRMSI PDCCH transmission may provide a location of resources for an RMSIPDSCH transmission that provides system information parameters. The UEmay initiate system access based on the DRS and received systeminformation.

In some cases, a UE may monitor multiple frequency sub-bands to try anddetect the DRS in the first beam sweeping procedure. In other cases, aUE may monitor only one frequency sub-band, or a subset of the multiplefrequency sub-bands used in the first beam sweeping procedure. In somecases, a UE may monitor multiple frequency sub-bands and combinemultiple instances of an SSB that is received via two or more of themonitored frequency sub-bands. In cases where the first beam sweepingprocedure does not use LBT procedures, the base station may transmit thebeams in accordance with a beam sequence of the first beam sweepingprocedure, and a location of resources for the second beam sweepingprocedure may be determined based on the transmission times in eachfrequency sub-band of the first beam sweeping procedure. In cases wherethe first beam sweeping procedure uses the LBT procedure, an SSB timewindow may be identified, and the beams of the first beam sweepingprocedure transmitted in each sub-band during an associated SSB timewindow of each frequency sub-band. In some cases, a number of quantizedstarting locations are available within each SSB time window at whichthe base station may start the first beam sweeping procedure. In somecases, the first beam sweeping procedure may transmit SSBs on apredetermined sequence of transmission beams that starts upon completingthe LBT procedure. In other cases, the first beam sweeping procedure maytransmit SSBs on the predetermined sequence of transmission beams thatstarts at a timing boundary within the associated SSB time window.

In some cases, the second beam sweeping procedure may start at a fixedtransmission time following the first beam sweeping procedure. In suchcases, if an LBT procedure fails prior to the second beam sweepingprocedure, the second beam sweeping procedure may be dropped andinitiated again according to a periodicity associated with the secondbeam sweeping procedure. In some cases, a second time window associatedwith the second beam sweeping procedure may be identified andtransmissions started within the second time window based on when theLBT procedure succeeds. In some cases, the control channel transmissionsin the second beam sweeping procedure may span multiple frequencysub-bands. In some cases, the frequency sub-bands of the second beamsweeping procedure may be indicated by the base station in the firstbeam sweeping procedure (e.g., based on a synchronization sequencepartition used for a synchronization signal transmitted in the firstbeam sweeping procedure, an explicit indication of a frequency offset,etc.).

Techniques as discussed herein may thus provide for efficient detectionof system information for use in initial access procedures (e.g., in arandom access channel (RACH) access procedure based on systeminformation obtained in SSB and RMSI transmissions). In some cases,transmission of the SSBs in a first beam sweeping procedure using asingle frequency sub-band may allow for increased power spectral density(PSD) of the SSB transmissions which may enhance the likelihood ofdetection at a UE. The control channel transmissions (e.g., RMSI PDCCHtransmissions) in the second beam sweeping procedure may span additionalfrequency sub-bands and thus carry additional information relative tothe SSB transmissions. The UE may identify beamforming characteristicsfor the second beam sweeping procedure based on the SSB, and thustransmission beams of the second beam sweeping procedure may havereduced PSD relative to the first beam sweeping procedure but stillprovide sufficient reliability of detection at the UE. Such techniquesmay thus enhance the efficiency and reliability of a wirelesscommunications system through more efficient beamformed communications.

Aspects of the disclosure are initially described in the context of awireless communications system. Several example resource configurationsfor SSB and RSMI beam sweeping procedures are then discussed. Aspects ofthe disclosure are further illustrated by and described with referenceto apparatus diagrams, system diagrams, and flowcharts that relate tostaggered SSBs in frequency sub-bands for beamformed wirelesscommunications.

FIG. 1 illustrates an example of a wireless communications system 100that supports staggered SSBs in frequency sub-bands for beamformedwireless communications in accordance with aspects of the presentdisclosure. The wireless communications system 100 includes basestations 105, UEs 115, and a core network 130. In some examples, thewireless communications system 100 may be a Long Term Evolution (LTE)network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, or a NewRadio (NR) network. In some cases, wireless communications system 100may support enhanced broadband communications, ultra-reliable (e.g.,mission critical) communications, low latency communications, orcommunications with low-cost and low-complexity devices.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Base stations 105 described herein mayinclude or may be referred to by those skilled in the art as a basetransceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a next-generation NodeB orgiga-NodeB (either of which may be referred to as a gNB), a Home NodeB,a Home eNodeB, or some other suitable terminology. Wirelesscommunications system 100 may include base stations 105 of differenttypes (e.g., macro or small cell base stations). The UEs 115 describedherein may be able to communicate with various types of base stations105 and network equipment including macro eNBs, small cell eNBs, gNBs,relay base stations, and the like.

Each base station 105 may be associated with a particular geographiccoverage area 110 in which communications with various UEs 115 issupported. Each base station 105 may provide communication coverage fora respective geographic coverage area 110 via communication links 125,and communication links 125 between a base station 105 and a UE 115 mayutilize one or more carriers. Communication links 125 shown in wirelesscommunications system 100 may include uplink transmissions from a UE 115to a base station 105, or downlink transmissions from a base station 105to a UE 115. Downlink transmissions may also be called forward linktransmissions while uplink transmissions may also be called reverse linktransmissions.

The geographic coverage area 110 for a base station 105 may be dividedinto sectors making up a portion of the geographic coverage area 110,and each sector may be associated with a cell. For example, each basestation 105 may provide communication coverage for a macro cell, a smallcell, a hot spot, or other types of cells, or various combinationsthereof. In some examples, a base station 105 may be movable andtherefore provide communication coverage for a moving geographiccoverage area 110. In some examples, different geographic coverage areas110 associated with different technologies may overlap, and overlappinggeographic coverage areas 110 associated with different technologies maybe supported by the same base station 105 or by different base stations105. The wireless communications system 100 may include, for example, aheterogeneous LTE/LTE-A/LTE-A Pro or NR network in which different typesof base stations 105 provide coverage for various geographic coverageareas 110.

The term “cell” refers to a logical communication entity used forcommunication with a base station 105 (e.g., over a carrier), and may beassociated with an identifier for distinguishing neighboring cells(e.g., a physical cell identifier (PCID), a virtual cell identifier(VCID)) operating via the same or a different carrier. In some examples,a carrier may support multiple cells, and different cells may beconfigured according to different protocol types (e.g., machine-typecommunication (MTC), narrowband Internet-of-Things (NB-IoT), enhancedmobile broadband (eMBB), or others) that may provide access fordifferent types of devices. In some cases, the term “cell” may refer toa portion of a geographic coverage area 110 (e.g., a sector) over whichthe logical entity operates.

UEs 115 may be dispersed throughout the wireless communications system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile device, a wireless device, a remote device, ahandheld device, or a subscriber device, or some other suitableterminology, where the “device” may also be referred to as a unit, astation, a terminal, or a client. A UE 115 may also be a personalelectronic device such as a cellular phone, a personal digital assistant(PDA), a tablet computer, a laptop computer, or a personal computer. Insome examples, a UE 115 may also refer to a wireless local loop (WLL)station, an Internet of Things (IoT) device, an Internet of Everything(IoE) device, or an MTC device, or the like, which may be implemented invarious articles such as appliances, vehicles, meters, or the like.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices, and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay that information to acentral server or application program that can make use of theinformation or present the information to humans interacting with theprogram or application. Some UEs 115 may be designed to collectinformation or enable automated behavior of machines. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples half-duplexcommunications may be performed at a reduced peak rate. Other powerconservation techniques for UEs 115 include entering a power saving“deep sleep” mode when not engaging in active communications, oroperating over a limited bandwidth (e.g., according to narrowbandcommunications). In some cases, UEs 115 may be designed to supportcritical functions (e.g., mission critical functions), and a wirelesscommunications system 100 may be configured to provide ultra-reliablecommunications for these functions.

In some cases, a UE 115 may also be able to communicate directly withother UEs 115 (e.g., using a peer-to-peer (P2P) or device-to-device(D2D) protocol). One or more of a group of UEs 115 utilizing D2Dcommunications may be within the geographic coverage area 110 of a basestation 105. Other UEs 115 in such a group may be outside the geographiccoverage area 110 of a base station 105, or be otherwise unable toreceive transmissions from a base station 105. In some cases, groups ofUEs 115 communicating via D2D communications may utilize a one-to-many(1:M) system in which each UE 115 transmits to every other UE 115 in thegroup. In some cases, a base station 105 facilitates the scheduling ofresources for D2D communications. In other cases, D2D communications arecarried out between UEs 115 without the involvement of a base station105.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., via an S1, N2, N3, orother interface). Base stations 105 may communicate with one anotherover backhaul links 134 (e.g., via an X2, Xn, or other interface) eitherdirectly (e.g., directly between base stations 105) or indirectly (e.g.,via core network 130).

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC), which may include at least one mobilitymanagement entity (MME), at least one serving gateway (S-GW), and atleast one Packet Data Network (PDN) gateway (P-GW). The MME may managenon-access stratum (e.g., control plane) functions such as mobility,authentication, and bearer management for UEs 115 served by basestations 105 associated with the EPC. User IP packets may be transferredthrough the S-GW, which itself may be connected to the P-GW. The P-GWmay provide IP address allocation as well as other functions. The P-GWmay be connected to the network operators IP services. The operators IPservices may include access to the Internet, Intranet(s), an IPMultimedia Subsystem (IMS), or a Packet-Switched (PS) Streaming Service.

At least some of the network devices, such as a base station 105, mayinclude subcomponents such as an access network entity, which may be anexample of an access node controller (ANC). Each access network entitymay communicate with UEs 115 through a number of other access networktransmission entities, which may be referred to as a radio head, a smartradio head, or a transmission/reception point (TRP). In someconfigurations, various functions of each access network entity or basestation 105 may be distributed across various network devices (e.g.,radio heads and access network controllers) or consolidated into asingle network device (e.g., a base station 105).

Wireless communications system 100 may operate using one or morefrequency bands, typically in the range of 300 megahertz (MHz) to 300gigahertz (GHz). Generally, the region from 300 MHz to 3 GHz is known asthe ultra-high frequency (UHF) region or decimeter band, since thewavelengths range from approximately one decimeter to one meter inlength. UHF waves may be blocked or redirected by buildings andenvironmental features. However, the waves may penetrate structuressufficiently for a macro cell to provide service to UEs 115 locatedindoors. Transmission of UHF waves may be associated with smallerantennas and shorter range (e.g., less than 100 km) compared totransmission using the smaller frequencies and longer waves of the highfrequency (HF) or very high frequency (VHF) portion of the spectrumbelow 300 MHz.

Wireless communications system 100 may also operate in a super highfrequency (SHF) region using frequency bands from 3 GHz to 30 GHz, alsoknown as the centimeter band. The SHF region includes bands such as the5 GHz industrial, scientific, and medical (ISM) bands, which may be usedopportunistically by devices that may be capable of toleratinginterference from other users.

Wireless communications system 100 may also operate in an extremely highfrequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz),also known as the millimeter band. In some examples, wirelesscommunications system 100 may support millimeter wave (mmW)communications between UEs 115 and base stations 105, and EHF antennasof the respective devices may be even smaller and more closely spacedthan UHF antennas. In some cases, this may facilitate use of antennaarrays within a UE 115. However, the propagation of EHF transmissionsmay be subject to even greater atmospheric attenuation and shorter rangethan SHF or UHF transmissions. Techniques disclosed herein may beemployed across transmissions that use one or more different frequencyregions, and designated use of bands across these frequency regions maydiffer by country or regulating body.

In some cases, wireless communications system 100 may utilize bothlicensed and unlicensed radio frequency spectrum bands. For example,wireless communications system 100 may employ License Assisted Access(LAA), LTE-Unlicensed (LTE-U) radio access technology, or NR technologyin an unlicensed band such as the 5 GHz ISM band. When operating inunlicensed radio frequency spectrum bands, wireless devices such as basestations 105 and UEs 115 may employ LBT procedures to ensure a frequencychannel is clear before transmitting data. In some cases, operations inunlicensed bands may be based on a carrier aggregation configuration inconjunction with component carriers operating in a licensed band (e.g.,LAA). Operations in unlicensed spectrum may include downlinktransmissions, uplink transmissions, peer-to-peer transmissions, or acombination of these. Duplexing in unlicensed spectrum may be based onfrequency division duplexing (FDD), time division duplexing (TDD), or acombination of both.

In some examples, base station 105 or UE 115 may be equipped withmultiple antennas, which may be used to employ techniques such astransmit diversity, receive diversity, multiple-input multiple-output(MIMO) communications, or beamforming. For example, wirelesscommunications system 100 may use a transmission scheme between atransmitting device (e.g., a base station 105) and a receiving device(e.g., a UE 115), where the transmitting device is equipped withmultiple antennas and the receiving device is equipped with one or moreantennas. MIMO communications may employ multipath signal propagation toincrease the spectral efficiency by transmitting or receiving multiplesignals via different spatial layers, which may be referred to asspatial multiplexing. The multiple signals may, for example, betransmitted by the transmitting device via different antennas ordifferent combinations of antennas. Likewise, the multiple signals maybe received by the receiving device via different antennas or differentcombinations of antennas. Each of the multiple signals may be referredto as a separate spatial stream, and may carry bits associated with thesame data stream (e.g., the same codeword) or different data streams.Different spatial layers may be associated with different antenna portsused for channel measurement and reporting. MIMO techniques includesingle-user MIMO (SU-MIMO) where multiple spatial layers are transmittedto the same receiving device, and multiple-user MIMO (MU-MIMO) wheremultiple spatial layers are transmitted to multiple devices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105 or a UE 115) to shape orsteer an antenna beam (e.g., a transmit beam or receive beam) along aspatial path between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that signals propagating atparticular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying certain amplitude and phase offsets to signals carried via eachof the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

In one example, a base station 105 may use multiple antennas or antennaarrays to conduct beamforming operations for directional communicationswith a UE 115. For instance, some signals (e.g., synchronizationsignals, reference signals, beam selection signals, or other controlsignals) may be transmitted by a base station 105 multiple times indifferent directions, which may include a signal being transmittedaccording to different beamforming weight sets associated with differentdirections of transmission. Transmissions in different beam directionsmay be used to identify (e.g., by the base station 105 or a receivingdevice, such as a UE 115) a beam direction for subsequent transmissionand/or reception by the base station 105.

Some signals, such as data signals associated with a particularreceiving device, may be transmitted by a base station 105 in a singlebeam direction (e.g., a direction associated with the receiving device,such as a UE 115). In some examples, the beam direction associated withtransmissions along a single beam direction may be determined based on asignal that was transmitted in different beam directions. For example, aUE 115 may receive one or more of the signals transmitted by the basestation 105 in different directions, and the UE 115 may report to thebase station 105 an indication of the signal it received with a highestsignal quality, or an otherwise acceptable signal quality. Althoughthese techniques are described with reference to signals transmitted inone or more directions by a base station 105, a UE 115 may employsimilar techniques for transmitting signals multiple times in differentdirections (e.g., for identifying a beam direction for subsequenttransmission or reception by the UE 115), or transmitting a signal in asingle direction (e.g., for transmitting data to a receiving device).

A receiving device (e.g., a UE 115, which may be an example of a mmWreceiving device) may try multiple receive beams when receiving varioussignals from the base station 105, such as synchronization signals,reference signals, beam selection signals, or other control signals. Forexample, a receiving device may try multiple receive directions byreceiving via different antenna subarrays, by processing receivedsignals according to different antenna subarrays, by receiving accordingto different receive beamforming weight sets applied to signals receivedat a plurality of antenna elements of an antenna array, or by processingreceived signals according to different receive beamforming weight setsapplied to signals received at a plurality of antenna elements of anantenna array, any of which may be referred to as “listening” accordingto different receive beams or receive directions. In some examples areceiving device may use a single receive beam to receive along a singlebeam direction (e.g., when receiving a data signal). The single receivebeam may be aligned in a beam direction determined based on listeningaccording to different receive beam directions (e.g., a beam directiondetermined to have a highest signal strength, highest signal-to-noiseratio, or otherwise acceptable signal quality based on listeningaccording to multiple beam directions).

In some cases, the antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays, which may support MIMOoperations, or transmit or receive beamforming. For example, one or morebase station antennas or antenna arrays may be co-located at an antennaassembly, such as an antenna tower. In some cases, antennas or antennaarrays associated with a base station 105 may be located in diversegeographic locations. A base station 105 may have an antenna array witha number of rows and columns of antenna ports that the base station 105may use to support beamforming of communications with a UE 115.Likewise, a UE 115 may have one or more antenna arrays that may supportvarious MIMO or beamforming operations.

In some cases, wireless communications system 100 may be a packet-basednetwork that operate according to a layered protocol stack. In the userplane, communications at the bearer or Packet Data Convergence Protocol(PDCP) layer may be IP-based. A Radio Link Control (RLC) layer mayperform packet segmentation and reassembly to communicate over logicalchannels. A Medium Access Control (MAC) layer may perform priorityhandling and multiplexing of logical channels into transport channels.The MAC layer may also use hybrid automatic repeat request (HARQ) toprovide retransmission at the MAC layer to improve link efficiency. Inthe control plane, the Radio Resource Control (RRC) protocol layer mayprovide establishment, configuration, and maintenance of an RRCconnection between a UE 115 and a base station 105 or core network 130supporting radio bearers for user plane data. At the Physical layer,transport channels may be mapped to physical channels.

In some cases, UEs 115 and base stations 105 may support retransmissionsof data to increase the likelihood that data is received successfully.HARQ feedback is one technique of increasing the likelihood that data isreceived correctly over a communication link 125. HARQ may include acombination of error detection (e.g., using a cyclic redundancy check(CRC)), forward error correction (FEC), and retransmission (e.g.,automatic repeat request (ARQ)). HARQ may improve throughput at the MAClayer in poor radio conditions (e.g., signal-to-noise conditions). Insome cases, a wireless device may support same-slot HARQ feedback, wherethe device may provide HARQ feedback in a specific slot for datareceived in a previous symbol in the slot. In other cases, the devicemay provide HARQ feedback in a subsequent slot, or according to someother time interval.

Time intervals in LTE or NR may be expressed in multiples of a basictime unit, which may, for example, refer to a sampling period of T_(s)=1/30,720,000 seconds. Time intervals of a communications resource may beorganized according to radio frames each having a duration of 10milliseconds (ms), where the frame period may be expressed asT_(f)=307,200 T_(s). The radio frames may be identified by a systemframe number (SFN) ranging from 0 to 1023. Each frame may include 10subframes numbered from 0 to 9, and each subframe may have a duration of1 ms. A subframe may be further divided into 2 slots each having aduration of 0.5 ms, and each slot may contain 6 or 7 modulation symbolperiods (e.g., depending on the length of the cyclic prefix prepended toeach symbol period). Excluding the cyclic prefix, each symbol period maycontain 2048 sampling periods. In some cases, a subframe may be thesmallest scheduling unit of the wireless communications system 100, andmay be referred to as a transmission time interval (TTI). In othercases, a smallest scheduling unit of the wireless communications system100 may be shorter than a subframe or may be dynamically selected (e.g.,in bursts of shortened TTIs (sTTIs) or in selected component carriersusing sTTIs).

In some wireless communications systems, a slot may further be dividedinto multiple mini-slots containing one or more symbols. In someinstances, a symbol of a mini-slot or a mini-slot may be the smallestunit of scheduling. Each symbol may vary in duration depending on thesubcarrier spacing or frequency band of operation, for example. Further,some wireless communications systems may implement slot aggregation inwhich multiple slots or mini-slots are aggregated together and used forcommunication between a UE 115 and a base station 105.

The term “carrier” refers to a set of radio frequency spectrum resourceshaving a defined physical layer structure for supporting communicationsover a communication link 125. For example, a carrier of a communicationlink 125 may include a portion of a radio frequency spectrum band thatis operated according to physical layer channels for a given radioaccess technology. Each physical layer channel may carry user data,control information, or other signaling. A carrier may be associatedwith a pre-defined frequency channel (e.g., an evolved universal mobiletelecommunications system terrestrial radio access (E-UTRA) absoluteradio frequency channel number (EARFCN)), and may be positionedaccording to a channel raster for discovery by UEs 115. Carriers may bedownlink or uplink (e.g., in an FDD mode), or be configured to carrydownlink and uplink communications (e.g., in a TDD mode). In someexamples, signal waveforms transmitted over a carrier may be made up ofmultiple sub-carriers (e.g., using multi-carrier modulation (MCM)techniques such as orthogonal frequency division multiplexing (OFDM) ordiscrete Fourier transform spread OFDM (DFT-s-OFDM)).

The organizational structure of the carriers may be different fordifferent radio access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR).For example, communications over a carrier may be organized according toTTIs or slots, each of which may include user data as well as controlinformation or signaling to support decoding the user data. A carriermay also include dedicated acquisition signaling (e.g., synchronizationsignals or system information, etc.) and control signaling thatcoordinates operation for the carrier. In some examples (e.g., in acarrier aggregation configuration), a carrier may also have acquisitionsignaling or control signaling that coordinates operations for othercarriers.

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. In some examples, controlinformation transmitted in a physical control channel may be distributedbetween different control regions in a cascaded manner (e.g., between acommon control region or common search space and one or more UE-specificcontrol regions or UE-specific search spaces).

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum, and in some examples the carrier bandwidth may bereferred to as a “system bandwidth” of the carrier or the wirelesscommunications system 100. For example, the carrier bandwidth may be oneof a number of predetermined bandwidths for carriers of a particularradio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 MHz). Insome examples, each served UE 115 may be configured for operating overportions or all of the carrier bandwidth. In other examples, some UEs115 may be configured for operation using a narrowband protocol typethat is associated with a predefined portion or range (e.g., set ofsubcarriers or RBs) within a carrier (e.g., “in-band” deployment of anarrowband protocol type).

In a system employing MCM techniques, a resource element may consist ofone symbol period (e.g., a duration of one modulation symbol) and onesubcarrier, where the symbol period and subcarrier spacing are inverselyrelated. The number of bits carried by each resource element may dependon the modulation scheme (e.g., the order of the modulation scheme).Thus, the more resource elements that a UE 115 receives and the higherthe order of the modulation scheme, the higher the data rate may be forthe UE 115. In MIMO systems, a wireless communications resource mayrefer to a combination of a radio frequency spectrum resource, a timeresource, and a spatial resource (e.g., spatial layers), and the use ofmultiple spatial layers may further increase the data rate forcommunications with a UE 115.

Devices of the wireless communications system 100 (e.g., base stations105 or UEs 115) may have a hardware configuration that supportscommunications over a particular carrier bandwidth, or may beconfigurable to support communications over one of a set of carrierbandwidths. In some examples, the wireless communications system 100 mayinclude base stations 105 and/or UEs 115 that support simultaneouscommunications via carriers associated with more than one differentcarrier bandwidth.

Wireless communications system 100 may support communication with a UE115 on multiple cells or carriers, a feature which may be referred to ascarrier aggregation or multi-carrier operation. A UE 115 may beconfigured with multiple downlink component carriers and one or moreuplink component carriers according to a carrier aggregationconfiguration. Carrier aggregation may be used with both FDD and TDDcomponent carriers.

In some cases, one or more of the base stations 105 may use beamformingfor communications with one or more UEs 115. In some cases, basestations 105 that use beamforming may transmit SSBs and RMSI viamultiple transmission beams in a beam sweeping procedure. The SSBtransmissions, in some cases, may be transmitted in an SSB beam sweepingprocedure in which beam sweeping is performed separately duringstaggered, non-overlapping time periods for each frequency sub-band ofthe number of frequency sub-bands. In some cases, each of the of SSBsindicates a reference timing of the base station that is used toidentify a set of resources (e.g., a CORESET) for RMSI PDCCHtransmissions. In some cases, a base station 105 transmitting the SSBsand RMSI PDCCH transmissions may perform an LBT procedure prior totransmitting the SSBs and the RMSI PDCCH transmissions. In other cases,the SSBs may be transmitted in LBT-free transmissions.

FIG. 2 illustrates an example of a wireless communications system 200that supports staggered SSBs in frequency sub-bands for beamformedwireless communications in accordance with aspects of the presentdisclosure. In some examples, wireless communications system 200 mayimplement aspects of wireless communications system 100. The wirelesscommunications system 200 may include base station 105-a and UE 115-a,which may be examples of a base station 105 and a UE 115, as describedwith reference to FIG. 1.

Base station 105-a may provide network coverage for geographic coveragearea 110-a. Base station 105-a and UE 115-a may communicate usingbeamformed or directional transmissions that carry uplink and downlinkcommunications between the UE 115-a and the base station 105-a. Whenperforming initial access, the UE 115-a may monitor (e.g., via adownlink or receive beam 210) for system information from the basestation 105-a that may be transmitted via multiple transmission beams205 in a beam sweeping procedure. In some cases, the UE 115-a maymonitor for transmissions from the base station 105-a and identify oneor more beams 205 that have channel characteristics that would support aconnection (e.g., based on a reference signal received power (RSRP) orsignal-to-noise ratio (SNR) associated with one or more detectedtransmission beams 205). In some cases, the UE 115-a and base station105-a may use corresponding beamforming parameters associated with aparticular transmission beam to configure receive hardware fortransmitting/receiving beamformed transmissions in which a beam pairlink may have coupled transmission beams with corresponding beamformingparameters. The beamforming parameters may include a particular spatialdomain filter for uplink or downlink communications that is associatedwith a particular transmission beam. In cases with coupled transmissionbeams, the beamforming parameters of an uplink beam may be determinedbased on one or more reference signals that are received on a selecteddownlink beam 205 which is quasi co-located (QCL) with the uplink beam.Two antenna ports are said to be QCL if properties of the channel overwhich a symbol on one antenna port is conveyed can be inferred from thechannel over which a symbol on the other antenna port is conveyed. Insome cases, QCL may apply to a spatial receive parameter, which may bereferred to as QCL-TypeD.

In some cases, base station 105-a may perform multiple beam sweepingprocedures that provide system information that may be used by the UE115-a in an initial access procedure. In some cases, the base station105-a may transmit SSBs using transmission beams 205 in a first beamsweeping procedure and may transmit RMSI PDCCH transmissions usingtransmission beams 205 in a second beam sweeping procedure. The SSBtransmissions, in some cases, may be transmitted in the beam sweepingprocedure using transmission beams that span a first frequency sub-bandof a number of available frequency sub-bands, followed by one or moreadditional transmissions in the beam sweeping procedure that span one ormore additional frequency sub-bands of the available frequencysub-bands. The RMSI PDCCH transmissions may use transmission beams thatspan two or more of the frequency sub-bands.

Such transmissions using different frequency sub-bands may allow for thebase station 105-a to transmit the SSBs at a relatively higher PSD thatmay enhance the detectability of the SSBs at the UE 115-a. In somecases, the transmission beams 205 may use relatively high frequencybands, such as high-band mmW frequencies in the 60-100 GHz range offrequencies (e.g., the “60 GHz band”, which refers to 57-64 & 64-71 GHzbands). Such frequency bands may be unlicensed, and thus differenttransmitters may share the frequencies in accordance with establishedprocedures that provide for fair access to the spectrum, such as LBTprocedures. Additionally, such shared frequencies may also becharacterized by relatively low transmit power limits (e.g., 13 dBm/MHzwith a channelization of 2 GHz, with a maximum Effective IsotropicRadiated Power (EIRP) of 40 dBm; or an average EIRP of 40 dBm and a peakEIRP of 43 dBm). In some cases, such as in the 60 GHz band, up to sevenchannels of two GHz each may be present (i.e., in the 57-71 GHz range).However, in cases with a transmit power of 13 dBm/MHz, a total power of46 dBm over 2 GHz, or a total power of 54.5 dBm over 14 GHz (for seven 2GHz carriers), would exceed regulatory limits. Techniques such asdiscussed herein may provide for enhanced PSD for initial transmissions,while complying with such regulatory requirements. Further, in somecases, LBT may be necessary for such transmissions due to regulatoryrequirements, and techniques as discussed herein may provide forefficient detection of beamformed transmissions based on when LBTclears.

In some cases, beamforming may be used in such relatively highfrequencies which may provide focused beams having a relatively narrowcoverage area that may enhance the distance from the base station 105-aat which a signal may be received and also reduce the likelihood of anLBT failure due to the relatively narrow beam. Further, techniques suchas discussed herein may provide enhanced and reliable detection ofsignals for initial system access. In some cases, the base station 105-amay transmit SSB transmissions using non-overlapping staggered beamsweeping transmissions in multiple frequency sub-bands, followed by aseparate beam sweeping procedure in which the base station 105-a maytransmit RMSI PDCCH transmissions using resources that may be determinedby the UE 115-a based on the detected SSB transmission, in which theRMSI bandwidth may not match the SSB bandwidth and the timing of theRMSI PDCCH transmissions may float within a transmission window.Additionally or alternatively, the base station 105-a may transmit SSBtransmissions in a floating SSB time window on each of the frequencysub-bands. Examples of such techniques are discussed with respect toFIGS. 3 through 6.

FIG. 3 illustrates an example of an SSB and RMSI resource configuration300 that supports staggered SSBs in frequency sub-bands for beamformedwireless communications in accordance with aspects of the presentdisclosure. In some examples, SSB and RMSI resource configuration 300may implement aspects of wireless communications system 100 or 200. Inthis example, a base station and UE (which may be examples of basestations 105 or UEs 115 of FIG. 1 or 2) may perform beamformedtransmissions in a frequency band 305. In some cases, the frequency band305 may be a high-band mmW frequency band.

In this example, a number of frequency sub-bands may be configured,including a first sub-band 310-a (F1), a second sub-band 310-b (F2), athird sub-band 310-c (F3), and a fourth sub-band 310-d (F4). While fourfrequency sub-bands 310 are illustrated in FIG. 3, other numbers offrequency sub-bands may be used, with the example of four sub-bandsprovided for purposes of illustration and discussion only. In thisexample, the base station may transmit a first instance of beamformedSSBs 315-a via an SSB beam sweeping procedure using the first frequencysub-band 310-a, a second instance of beamformed SSBs 315-b via the SSBbeam sweeping procedure using the second frequency sub-band 310-b, athird instance of beamformed SSBs 315-c via the SSB beam sweepingprocedure using the third frequency sub-band 310-c, and a fourthinstance of beamformed SSBs 315-d via the SSB beam sweeping procedureusing the fourth frequency sub-band 310-d.

In this example, each of the beamformed SSBs 315 may provide anindication of a same set of resources (e.g., a CORESET) for the RMSIbeam sweeping procedure used to transmit a beamformed RMSI controlchannel transmissions 320 (e.g., RMSI PDCCH transmissions that mayindicate resources for an RMSI PDSCH transmission that provides systeminformation). In this example, the RMSI beam sweeping procedure of thebeamformed RMSI control channel transmissions 320 may be transmittedduring an RMSI window 325 via the same set of transmission beams as usedfor SSB beam sweeping procedure, but may be transmitted usingfrequencies that span the first frequency sub-band 310-a through thethird frequency sub-band 310-c. In this example, SSBs 315 and RMSIcontrol channel transmissions 320 may be transmitted according to apredetermined periodicity for purposes of providing detection by one ormore UEs that may seek to gain network access. In such cases, additionalinstances of beamformed SSBs 315 may be transmitted followed byadditional instances of beamformed RMSI control channel transmissions320 that may span different frequency sub-bands than the SSBtransmissions. While beamformed RMSI control channel transmissions 320are illustrated as spanning three frequency sub-bands 310, suchtransmissions may span more or fewer frequency sub-bands in other cases.

In this example, the staggered SSBs 315 may thus be cycled through eachof the multiple predefined frequency sub-bands 310. In such a manner, asone SSB 315 is transmitted at a time in one associated frequencysub-band 310, the PSD of the SSB 315 transmissions may be maximized foreach frequency sub-band 310 and transmissions of SSBs 315 are notlimited to one sub-band 310. In some cases, each of the SSBs 315 mayprovide a timing indication that indicates a timing associated with theRMSI control channel transmission 320 resources and may also provide afrequency indication that indicates a frequency associated with the RMSIcontrol channel transmission 320 resources. In the example of FIG. 3,each SSB 315 may indicate system timing relative to a reference timingthat is defined as an SSB starting point 330 of a designated referencesub-band (e.g., the first frequency sub-band 310-a).

In some cases, SSBs 315 that are transmitted in each of the frequencysub-bands 310 may each include a PBCH payload that is associated with atime offset of the frequency sub-band 310 used to transmit the SSB 315.For example, the SSB PBCH may indicate T0 for the first frequencysub-band 310-a, may indicate T1 for the second frequency sub-band 310-b,may indicate T2 for the third frequency sub-band 310-c, and so on. Eachof the different T0, T1, and T2 values may indicate a timing of the RMSIwindow 325 relative to the reference timing of the SSB starting point330. Such techniques may allow the base station to change the order inwhich the frequency sub-bands 310 are cycled in an SSB beam sweepingprocedure. In other examples, the PBCH payload of each SSB 315 may bethe same, but the SSBs 315 may be interpreted differently (e.g., basedon a predetermined timing offset associated with each frequency sub-band310), which may allow for combining of PBCHs at a UE that can monitormultiple frequency sub-bands 310.

By transmitting the beamformed SSBs 315 using one frequency sub-band 310at a time, the SSB PSD may be enhanced for that sub-band, which mayenhance detectability at the UE. Further, all UEs seeking to access thebase station may run a searcher at one or more of the frequencysub-bands 310 and detect an SSB 315 that is transmitted on that sub-band310, and thus sub-band diversity of the SSBs 315 may further enhance SSBdetectability. In some cases, a UE may monitor multiple of the sub-bands310 and detect multiple instances of SSBs 315, which in some cases maybe combined at the UE to further enhance detectability of the SSBs 315at the UE. The beamformed RMSI control channel transmissions 320 may betransmitted using any of the frequency sub-bands 310. In some cases, thebase station may select the frequency sub-bands 310 for the beamformedRMSI control channel transmissions 320 based on one or more channelmetrics associated with each of the frequency sub-bands 310, such as along term interference metric associated with LBT procedures performedat each sub-band 310.

In this example, the beamformed SSBs 315 may be transmitted with no LBT.In such cases, the beamformed SSBs 315 may comply with parameters for anLBT-free or LBT-exempt transmission. In other cases, the beamformed SSBs315 may be transmitted using a reduced contention window LBT procedure(e.g., a Cat2 LBT) and in the event that the LBT fails, that particularinstance of the beamformed SSBs 315 may be dropped. Further, in thisexample, the beamformed RMSI control channel transmissions 320 may betransmitted based on passing an LBT procedure. In some cases, asindicated above, the beamformed RMSI control channel transmissions 320may be transmitted at a fixed time relative to the SSB starting point330, and an instance of the RMSI control channel transmissions 320 maybe dropped if LBT fails. In other cases, such as in the example shown inFIG. 3, an RMSI window 325 may be provided and the beamformed RMSIcontrol channel transmissions 320 may be transmitted within the RMSIwindow 325 upon successful LBT completion (e.g., the successfulcompletion of a Cat4 LBT procedure). In the example of FIG. 3., thebeamformed RMSI control channel transmissions 320 may start at thebeginning of the associated RMSI window 325, although in other casessuch transmissions may start later within the RMSI window 325 once LBTclears. In such cases, a UE may search for the RMSI control channeltransmissions 320 within the RMSI window 325, and may discontinuesearching for the RMSI control channel transmissions 320 upon detectionof RMSI or the expiration of the RMSI window 325. In some cases, thestarting and ending points of the RMSI window 325 may be determinedbased on a receipt time of the particular transmission beam on which theSSB is detected by the UE and a timing offset indicated in the SSB(e.g., relative to a frame boundary or the SSB starting point 330).

As indicated in the example of FIG. 3, the beamformed RMSI controlchannel transmissions 320 may use different frequency sub-bands 310 thanthe SSBs 315. In some cases, the frequency location of the RMSI controlchannel transmissions 320 may be indicated by the SSBs 315. In someexamples, a payload transmitted in the SSBs 315 (e.g., in a PBCH of theSSB) may provide an explicit frequency offset for the RMSI controlchannel transmissions 320. In other cases, the SSBs 315 may provide animplicit indication of the frequency offset for the RMSI control channeltransmissions 320. For example, a sequence of one or more of the PSS orSSS of the SSBs 315 may be partitioned with different partitions mappedto different frequency offsets (e.g., 252 base station cell IDs may bemapped to 1008 PSS/SSS sequences to indicate one of four availablefrequency offsets). In other cases, RMSI control channel transmissions320 may also be fixed in predetermined frequency sub-bands 310, whichmay reduce flexibility of a base station to select sub-bands that may bemore favorable. The information from the beamformed SSBs 315 and thebeamformed RMSI control channel transmissions 320 may be used by a UE todetermine resources and timing for transmission of a random accessrequest to the base station to initiate system access, in some cases.

FIG. 4 illustrates an example of an SSB and RMSI resource configuration400 that supports staggered SSBs in frequency sub-bands for beamformedwireless communications in accordance with aspects of the presentdisclosure. In some examples, SSB and RMSI resource configuration 400may implement aspects of wireless communications system 100 or 200. Inthis example, a base station and UE (which may be examples of basestations 105 or UEs 115 of FIG. 1 or 2) may perform beamformedtransmissions in a frequency band 405. In some cases, the frequency band405 may be a high-band mmW frequency band. In this example, similarly asin the example of FIG. 3, a number of frequency sub-bands may beconfigured, including a first sub-band 410-a (F1), a second sub-band410-b (F2), a third sub-band 410-c (F3), and a fourth sub-band 410-d(F4). While four frequency sub-bands 410 are illustrated in FIG. 4,other numbers of frequency sub-bands may be used, with the example offour sub-bands provided for purposes of illustration and discussiononly.

In this example, similarly as with the example of FIG. 3, the basestation may transmit a first instance of beamformed SSBs 415-a via anSSB beam sweeping procedure using the first frequency sub-band 410-a,and the beamformed SSBs 415-a may provide an indication of resources forRMSI beam sweeping procedure in an RMSI window 435 used to transmitbeamformed RMSI control channel transmissions 430. The RMSI beamsweeping procedure of the beamformed RMSI control channel transmissions430 may be transmitted via the same set of transmission beams as usedfor SSB beam sweeping procedure, but may be transmitted usingfrequencies that span multiple of the frequency sub-bands 410.

In this example, again, the staggered SSBs 415 may be cycled througheach of the multiple predefined frequency sub-bands 410. In such amanner, as one SSB 415 is transmitted at a time in one associatedfrequency sub-band 410, the PSD of the SSB 415 transmissions may bemaximized for each frequency sub-band 410, and transmissions of SSBs 415are not limited to one sub-band 410. In this example, the base stationmay perform LBT prior to transmitting the SSBs 415, and in eachfrequency sub-band 410 an SSB window 425 may define a time period duringwhich the associated SSBs 415 may be transmitted by the base station. Insuch cases, the SSBs 415 may be transmitted within an SSB window 425,where the start of the SSBs 415 occurs after a successful LBT iscompleted within the SSB window 425. In this example, a first instanceof the SSBs 415-a may start following gap 420-a in a first SSB window425-a, a second instance of the SSBs 415-b and a third instance of theSSBs 415-c may each start at the beginning of their corresponding SSBwindows 425-b and 425-c, and a fourth instance of the SSBs 415-d may betransmitted following gap 420-b in a fourth SSB window 425-d. In somecases, the SSBs 415 may indicate resources for the beamformed RMSIcontrol channel transmissions 430. In some cases, as will be discussedin more detail with respect to FIG. 5, the time location of the RMSIcontrol channel transmissions may be indicated relative to a fixed SSBtime boundary or SSB starting point 427 or based on a relative locationof the SSBs 415 within the respective SSB window 425.

In some cases, SSBs 415 that are transmitted in each of the frequencysub-bands 410 may each include a PBCH payload that is associated with atime offset of the frequency sub-band 410 used to transmit the SSB 415.For example, the SSB PBCH may indicate T0 for the first frequencysub-band 410-a, may indicate T1 for the second frequency sub-band 410-b,may indicate T2 for the third frequency sub-band 410-c, and so on. Eachof the different T0, T1, and T2 values may indicate a timing of the RMSIwindow 435 relative to the reference timing of the SSB starting point427. Such techniques may allow the base station to change the order inwhich the frequency sub-bands 410 are cycled in an SSB beam sweepingprocedure. In some cases, each PBCH payload may indicate a value offloor(T/N), where T is a time of the associated SSB window 425 and mod Nis the repetition periodicity of the underlying SSB pattern, such thatthe SSB starting point 427 may be identified.

Additionally or alternatively, the beamformed RMSI control channeltransmissions 430 may be transmitted based on passing an LBT procedure,and an instance of the RMSI control channel transmissions 430 may bedropped if LBT fails. In some cases, such as illustrated in FIG. 4, anRMSI window 435 may be provided and the beamformed RMSI control channeltransmissions 430 may be transmitted within the RMSI window 435 uponsuccessful LBT completion (e.g., the successful completion of a Cat4 LBTprocedure). In the example of FIG. 4., the beamformed RMSI controlchannel transmissions 430 may start after time gap 440, within the RMSIwindow 435 once LBT clears. In such cases, a UE may search for the RMSIcontrol channel transmissions 430 within the RMSI window 435, and maydiscontinue searching for the RMSI control channel transmissions 430upon detection of RMSI or the expiration of the RMSI window 435.

As indicated in the example of FIG. 4, the beamformed RMSI controlchannel transmissions 430 may use different frequency sub-bands 410 thanthe SSBs 415. In some cases, the frequency location of the RMSI controlchannel transmissions 430 may be indicated by the SSBs 415. In someexamples, a payload transmitted in the SSBs 415 (e.g., in a PBCH of theSSB) may provide an explicit frequency offset for the RMSI controlchannel transmissions 430. In other cases, the SSBs 415 may provide animplicit indication of the frequency offset for the RMSI control channeltransmissions 430 (e.g., based on a partitioned PSS/SSS sequence. Theinformation from the beamformed SSBs 415 and the beamformed RMSI controlchannel transmissions 430, in some cases, may be used by a UE todetermine resources and timing for transmission of a random accessrequest to the base station to initiate system access.

In some cases, a start of the RMSI window 435 may either be fixed orvariable relative to SSB windows 425. In cases where the RMSI window 435is fixed relative to the SSB windows 425, the floating duration of theRMSI window 435 may be limited by the location of the SSBs 415 withinthe SSB windows 425, in order to keep latency from increasing. In caseswhere the RMSI window 435 is variable, the timing of the RMSI controlchannel transmissions 430 may be indicated using the floating locationof the SSBs 415. In some cases, as will be discussed in more detail withrespect to FIG. 5, a quantized number of available SSB startinglocations may be defined within the SSB windows 425 and a location ofthe RMSI window 435 may be identified based on which of the SSB startinglocations is used (e.g., explicitly indicated or implicitly indicatedsuch as by using PSS/SSS sequence partitions) within each of the SSBwindows 425. In other cases, the location of the RMSI window 435 may beidentified relative to the SSB starting point 427 (i.e., based on areference timing or frame boundary). Additionally, in some cases, thebase station may begin SSB transmissions with a first SSB on a firsttransmission beam (i.e., SSB0 on transmission beam 0). In other cases,the base station may begin SSB transmissions after LBT clearancestarting with SSB-K on transmission beam K, where K is the SSB index aspart of a pre-defined pattern relative to an SSB window 425 boundary orframe boundary, or SSB starting point 427. Examples of RMSI timing andSSB starting transmissions are discussed in more detail with respect toFIG. 5.

FIG. 5 illustrates an example of a floating resource configurations 500that supports staggered SSBs in frequency sub-bands for beamformedwireless communications in accordance with aspects of the presentdisclosure. In some examples, floating resource configurations 500 mayimplement aspects of wireless communications system 100 or 200. In thisexample, a first sub-band 505 is illustrated that may be used for an SSBbeam sweeping procedure to transmit SSBs 510, and additional frequencysub-bands of a staggered SSB beam sweeping procedure may use the same orsimilar techniques. In this example, SSBs 510 may be transmitted duringSSB window 525 following a successful LBT. As indicated above, in somecases a quantized number of available SSB starting locations 530 may bedefined within the SSB window 525 and a location of the RMSI window maybe identified based on which of the SSB starting locations 530 withinthe SSB window 525 is used. In some cases, the location within the SSBwindow 525 may be explicitly indicated (e.g., in a PBCH payload) orimplicitly indicated (e.g., using PSS/SSS sequence partitions). In othercases, the location of the RMSI window may be identified relative to theSSB window 525 boundary (i.e., based on a reference timing, frameboundary, or SSB starting time).

In some cases, the base station may use a floating SSB pattern 535 or afixed SSB pattern 545 to determine which SSB to begin transmittingfollowing successful LBT. In the floating SSB pattern 535, LBT may clearat time 540 and the base station may begin SSB transmissions with afirst SSB on a first transmission beam (i.e., SSB0 on transmission beam0) irrespective of a time within the SSB window 525 when the LBT clears.In the fixed SSB pattern 545, the base station may begin SSBtransmissions after LBT clearance at time 555 starting with SSB-K ontransmission beam K, where K is the SSB index as part of a pre-definedpattern relative to timing boundary 550, which may be a time associatedwith a start of the associated SSB window 525 or an SSB starting timeassociated with the SSB beam sweeping procedure. In some cases, SSBtiming may use additional bits to indicate a value of floor(T/N) where Tis time associated with the particular SSB window and mod N is therepetition periodicity of underlying SSB pattern.

FIG. 6 illustrates an example of a process flow 600 that supportsstaggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure. Insome examples, process flow 600 may implement aspects of wirelesscommunications system 100 or 200. In this example, process flow 600includes UE 115-b and base station 105-b, which may be examples of thecorresponding devices described with reference to FIGS. 1 and 2.

At 605, the base station 105-b may optionally perform an LBT procedure.In some cases, the LBT procedure may be performed before transmittingSSBs in an SSB beam sweep procedure. In some cases, the LBT proceduremay provide that the base station 105-b identifies a contention window(e.g., based on a type of LBT such as a Cat2 or Cat4 LBT that provideshorter or longer contention windows), and following the expiration ofthe contention window an energy measurement may be performed on thefrequency bands that are to be used for the SSB transmissions. If theenergy measurement is below a threshold value, it may indicate that noother transmitters are using the channel and the LBT clears and the basestation 105-b may begin transmitting. If the energy measurement is at orabove the threshold value, it may indicate that another transmitter isusing the channel and the base station 105-b may adjust the contentionwindow and attempt the LBT again following expiration of the contentionwindow, or drop transmissions on a particular band that fails LBT. Incases where the contention window is after the expiration of an SSBwindow, the base station 105-b may drop the SSB transmission, and asubsequent SSB beam sweeping procedure may be initiated based on an SSBbeam sweeping periodicity.

At 610, the base station 105-b may transmit SSBs via an SSB beamsweeping procedure on a first frequency sub-band. In cases where the LBTprocedure is used, the SSBs may be transmitted responsive to asuccessful LBT procedure. In some cases, a number of SSBs may betransmitted using a number of transmission beams in the SSB beam sweepprocedure. In this example, multiple other SSBs may be transmitted at615 through 620 on other frequency sub-bands at staggered times suchthat only one frequency sub-band at a time has an SSB transmission.

At 625, the UE 115-b may detect one or more of the SSBs from the basestation 105-b and identify RMSI resources (e.g., a CORESET fortransmission of RMSI PDCCH). In some cases, the UE 115-b may run asearcher to monitor for SSB transmissions via one or more of thefrequency sub-bands. In some cases, the UE 115-b may monitor for SSBs onmultiple sub-bands and combine multiple instances of SSBs. In somecases, the RMSI resources may be identified based on one or more of animplicit indication or an explicit indication, or both, provided withthe detected SSB. In some cases, the SSB may indicate time resources forthe RMSI, frequency resources for the RMSI, or both.

At 630, the base station 105-b may perform another LBT to determine ifthe frequency sub-bands associated with the RMSI control channeltransmissions (e.g., RMSI PDCCH transmissions) are clear for an RMSIbeam sweeping procedure. At 635, if the LBT procedure clears, the basestation 105-b transmits the RMSI control channel transmissions using theRMSI beam sweeping procedure. In some cases, the RMSI control channeltransmissions start after a successful LBT procedure within an RMSIwindow. In some cases, if the LBT fails, the base station 105-b may dropthe RMSI control channel transmissions. In cases where the base station105-b transmits the RMSI control channel transmissions, suchtransmissions may span two or more frequency sub-bands.

At 640, the UE 115-b may receive one or more of the RMSI control channeltransmissions and determine one or more initial access parameters forthe base station 105-b. In some cases, the RMSI control channeltransmissions may indicate a location for RMSI PDSCH transmissions thatinclude system information that, in conjunction with the SSB and RMSICORESET, provide parameters for initiating initial access. The one ormore initial access parameters may include, for example, RACH timing andresources for a random access request to be transmitted to the basestation 105-b. In some cases, the initial access parameters may includeone or more beamforming parameters associated with random accessresources for initial access. At 645, the UE 115-b and the base station105-b may perform the initial access procedure to establish a connectionbetween the UE 115-b and the base station 105-b.

FIG. 7 shows a block diagram 700 of a device 705 that supports staggeredSSBs in frequency sub-bands for beamformed wireless communications inaccordance with aspects of the present disclosure. The device 705 may bean example of aspects of a UE 115 as described herein. The device 705may include a receiver 710, a communications manager 715, and atransmitter 720. The device 705 may also include a processor. Each ofthese components may be in communication with one another (e.g., via oneor more buses).

The receiver 710 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to staggeredSSBs in frequency sub-bands for beamformed wireless communications,etc.). Information may be passed on to other components of the device705. The receiver 710 may be an example of aspects of the transceiver1020 described with reference to FIG. 10. The receiver 710 may utilize asingle antenna or a set of antennas.

The communications manager 715 may monitor one or more of a set offrequency sub-bands for an SSB from a base station, where each of theset of frequency sub-bands carries a non-overlapping instance of theSSB, receive a first instance of the SSB via at least a first frequencysub-band of the set of frequency sub-bands based on the monitoring,determine a reference timing of the base station based on one or more ofinformation from the first instance of the SSB or a frequency locationof the first frequency sub-band relative to a reference frequencysub-band of the set of frequency sub-bands, identify, based on thereference timing, a set of resources (e.g., a CORESET) for a controlchannel transmission from the base station, where the set of resourcesspans two or more of the set of frequency sub-bands, and receive thecontrol channel transmission (e.g., an RMSI PDCCH transmission) via theset of resources. The communications manager 715 may be an example ofaspects of the communications manager 1010 described herein.

The communications manager 715, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 715, or itssub-components may be executed by a general-purpose processor, a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), a field-programmable gate array (FPGA) or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed in the present disclosure.

The communications manager 715, or its sub-components, may be physicallylocated at various positions, including being distributed such thatportions of functions are implemented at different physical locations byone or more physical components. In some examples, the communicationsmanager 715, or its sub-components, may be a separate and distinctcomponent in accordance with aspects of the present disclosure. In someexamples, the communications manager 715, or its sub-components, may becombined with one or more other hardware components, including but notlimited to an input/output (I/O) component, a transceiver, a networkserver, another computing device, one or more other components describedin the present disclosure, or a combination thereof in accordance withaspects of the present disclosure.

The transmitter 720 may transmit signals generated by other componentsof the device 705. In some examples, the transmitter 720 may becollocated with a receiver 710 in a transceiver module. For example, thetransmitter 720 may be an example of aspects of the transceiver 1020described with reference to FIG. 10. The transmitter 720 may utilize asingle antenna or a set of antennas.

FIG. 8 shows a block diagram 800 of a device 805 that supports staggeredSSBs in frequency sub-bands for beamformed wireless communications inaccordance with aspects of the present disclosure. The device 805 may bean example of aspects of a device 705, or a UE 115 as described herein.The device 805 may include a receiver 810, a communications manager 815,and a transmitter 840. The device 805 may also include a processor. Eachof these components may be in communication with one another (e.g., viaone or more buses).

The receiver 810 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to staggeredSSBs in frequency sub-bands for beamformed wireless communications,etc.). Information may be passed on to other components of the device805. The receiver 810 may be an example of aspects of the transceiver1020 described with reference to FIG. 10. The receiver 810 may utilize asingle antenna or a set of antennas.

The communications manager 815 may be an example of aspects of thecommunications manager 715 as described herein. The communicationsmanager 815 may include a sub-band identification component 820, an SSBmonitoring manager 825, an SSB timing component 830, and an RMSImonitoring manager 835. The communications manager 815 may be an exampleof aspects of the communications manager 1010 described herein.

The sub-band identification component 820 may monitor one or more of aset of frequency sub-bands for an SSB from a base station, where each ofthe set of frequency sub-bands carries a non-overlapping instance of theSSB.

The SSB monitoring manager 825 may receive a first instance of the SSBvia at least a first frequency sub-band of the set of frequencysub-bands based on the monitoring.

The SSB timing component 830 may determine a reference timing of thebase station based on one or more of information from the first instanceof the SSB or a frequency location of the first frequency sub-bandrelative to a reference frequency sub-band of the set of frequencysub-bands.

The RMSI monitoring manager 835 may identify, based on the referencetiming, a set of resources for a control channel transmission from thebase station, where the set of resources spans two or more of the set offrequency sub-bands and receive the control channel transmission via theset of resources.

In some implementations, the actions performed by the sub-bandidentification component 820, the SSB monitoring manager 825, the SSBtiming component 830, and the RMSI monitoring manager 835, as describedherein, may facilitate the processor 1040, as described with referenceto FIG. 10, to more efficiently cause the device 805 to perform variousfunctions. For example, transmission of the SSBs in a first beamsweeping procedure using a single frequency sub-band may facilitaterelatively increased PSD of the SSB transmissions, which may accordinglyrelatively improve the likelihood that the device 805 successfullydetects the SSB. Control channel transmissions (e.g., RMSI PDCCHtransmissions) in a second beam sweeping procedure may span additionalfrequency sub-bands and thus carry additional information relative tothe SSB transmissions.

As such, the device 805 may identify beamforming characteristics for thesecond beam sweeping procedure based on the SSB, and thus transmissionbeams of the second beam sweeping procedure may have reduced PSDrelative to the first beam sweeping procedure while providing sufficientreliability for detection by the device 805. In using these beamformedcommunications techniques, the device 805 may communicate with the basestation with relatively greater efficiency and reliability, which maycorrespondingly reduce repeated transmissions and conserve frequency,time, and/or spatial resources. Accordingly, the device 805 may reduce anumber of processing operations at the processor and other components ofthe device 805, which may in turn provide power savings and conserveprocessing resources for the processor of the device 805.

The transmitter 840 may transmit signals generated by other componentsof the device 805. In some examples, the transmitter 840 may becollocated with a receiver 810 in a transceiver module. For example, thetransmitter 840 may be an example of aspects of the transceiver 1020described with reference to FIG. 10. The transmitter 840 may utilize asingle antenna or a set of antennas.

FIG. 9 shows a block diagram 900 of a communications manager 905 thatsupports staggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure. Thecommunications manager 905 may be an example of aspects of acommunications manager 715, a communications manager 815, or acommunications manager 1010 described herein. The communications manager905 may include a sub-band identification component 910, an SSBmonitoring manager 915, an SSB timing component 920, an RMSI monitoringmanager 925, and a beamforming manager 930. Each of these modules maycommunicate, directly or indirectly, with one another (e.g., via one ormore buses).

The sub-band identification component 910 may monitor one or more of aset of frequency sub-bands for an SSB from a base station, where each ofthe set of frequency sub-bands carries a non-overlapping instance of theSSB. In some cases, each frequency sub-band of the set of frequencysub-bands has a corresponding offset from the reference timing of thebase station.

The SSB monitoring manager 915 may receive a first instance of the SSBvia at least a first frequency sub-band of the set of frequencysub-bands based on the monitoring. In some examples, the SSB monitoringmanager 915 may monitor two or more of the set of frequency sub-bandsfor respective instances of the SSB. In some examples, the SSBmonitoring manager 915 may combine two or more instances of the SSB fromthe monitored two or more of the set of frequency sub-bands.

In some cases, each of the instances of the SSB transmitted via each ofthe set of frequency sub-bands indicates a same set of resources for thecontrol channel transmission from the base station. In some cases, anSSB payload of each instance of the SSB indicates the reference timingof the base station relative to the respective instance of the SSB.

The SSB timing component 920 may determine a reference timing of thebase station based on one or more of information from the first instanceof the SSB or a frequency location of the first frequency sub-bandrelative to a reference frequency sub-band of the set of frequencysub-bands. In some examples, the SSB timing component 920 may identify afixed time periodicity for monitoring the one or more of the set offrequency sub-bands for the SSB from the base station. In some examples,the SSB timing component 920 may identify an SSB time window formonitoring the one or more of the set of frequency sub-bands for the SSBfrom the base station.

The RMSI monitoring manager 925 may identify, based on the referencetiming, a set of resources for a control channel transmission from thebase station, where the set of resources spans two or more of the set offrequency sub-bands. In some examples, the RMSI monitoring manager 925may receive the control channel transmission via the set of resources.In some examples, the RMSI monitoring manager 925 may determine afrequency offset of the set of resources relative to the first frequencysub-band based on information provided by the first instance of the SSB.

In some cases, the set of resources includes a predetermined startingtime resource for the control channel transmission relative to thereference frequency sub-band of the set of frequency sub-bands. In somecases, the set of resources includes a control channel time windowduring which the UE is to monitor for the control channel transmission.In some cases, a duration of the control channel time window is based onan LBT procedure duration and a number of LBT attempts that the basestation is configured to perform before dropping the control channeltransmission.

The beamforming manager 930 may identify one or more transmission beamsthat are used to receive the SSB and system information. In some cases,the SSB is transmitted using an SSB beam sweeping procedure in which aseries of consecutive transmission beams within each frequency sub-bandeach carry a corresponding SSB, and where a same initial transmissionbeam of the series of consecutive transmission beams is usedirrespective of when the SSB beam sweeping procedure starts within theSSB time window. In some cases, the SSB is transmitted using an SSB beamsweeping procedure in which a series of consecutive transmission beamseach carry a corresponding SSB having an SSB index that indicates aposition of the SSB relative to a frame boundary within each frequencysub-band of the set of frequency sub-bands.

FIG. 10 shows a diagram of a system 1000 including a device 1005 thatsupports staggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure. Thedevice 1005 may be an example of or include the components of device705, device 805, or a UE 115 as described herein. The device 1005 mayinclude components for bi-directional voice and data communicationsincluding components for transmitting and receiving communications,including a communications manager 1010, an I/O controller 1015, atransceiver 1020, an antenna 1025, memory 1030, and a processor 1040.These components may be in electronic communication via one or morebuses (e.g., bus 1045).

The communications manager 1010 may monitor one or more of a set offrequency sub-bands for an SSB from a base station, where each of theset of frequency sub-bands carries a non-overlapping instance of theSSB, receive a first instance of the SSB via at least a first frequencysub-band of the set of frequency sub-bands based on the monitoring,determine a reference timing of the base station based on one or more ofinformation from the first instance of the SSB or a frequency locationof the first frequency sub-band relative to a reference frequencysub-band of the set of frequency sub-bands, identify, based on thereference timing, a set of resources for a control channel transmissionfrom the base station, where the set of resources spans two or more ofthe set of frequency sub-bands, and receive the control channeltransmission via the set of resources.

The I/O controller 1015 may manage input and output signals for thedevice 1005. The I/O controller 1015 may also manage peripherals notintegrated into the device 1005. In some cases, the I/O controller 1015may represent a physical connection or port to an external peripheral.In some cases, the I/O controller 1015 may utilize an operating systemsuch as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, oranother known operating system. In other cases, the I/O controller 1015may represent or interact with a modem, a keyboard, a mouse, atouchscreen, or a similar device. In some cases, the I/O controller 1015may be implemented as part of a processor. In some cases, a user mayinteract with the device 1005 via the I/O controller 1015 or viahardware components controlled by the I/O controller 1015.

The transceiver 1020 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 1020 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1020 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1025.However, in some cases the device may have more than one antenna 1025,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1030 may include random-access memory (RAM) and read-onlymemory (ROM). The memory 1030 may store computer-readable,computer-executable code 1035 including instructions that, whenexecuted, cause the processor to perform various functions describedherein. In some cases, the memory 1030 may contain, among other things,a basic input/output system (BIOS) which may control basic hardware orsoftware operation such as the interaction with peripheral components ordevices.

The processor 1040 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1040 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 1040. The processor 1040 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 1030) to cause the device 1005 to perform variousfunctions (e.g., functions or tasks supporting staggered SSBs infrequency sub-bands for beamformed wireless communications).

The code 1035 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1035 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1035 may not be directly executable by theprocessor 1040 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 11 shows a block diagram 1100 of a device 1105 that supportsstaggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure. Thedevice 1105 may be an example of aspects of a base station 105 asdescribed herein. The device 1105 may include a receiver 1110, acommunications manager 1115, and a transmitter 1120. The device 1105 mayalso include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 1110 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to staggeredSSBs in frequency sub-bands for beamformed wireless communications,etc.). Information may be passed on to other components of the device1105. The receiver 1110 may be an example of aspects of the transceiver1420 described with reference to FIG. 14. The receiver 1110 may utilizea single antenna or a set of antennas.

The communications manager 1115 may identify a set of frequencysub-bands for transmitting a set of SSBs via a set of transmission beamsin an SSB beam sweeping procedure, identify a set of resources fortransmitting a set of RMSI control channel transmissions via the set oftransmission beams in an RMSI beam sweeping procedure, where the set ofresources spans two or more of the set of frequency sub-bands, transmit,responsive to completing the LBT procedure, the set of RMSI controlchannel transmissions via the set of transmission beams in the RMSI beamsweeping procedure using the set of resources, transmit the set of SSBsvia the set of transmission beams in the SSB beam sweeping procedure ineach of the set of sub-bands, where the SSB beam sweeping procedure isperformed separately during non-overlapping time periods for eachfrequency sub-band of the set of frequency sub-bands, and where each ofthe set of SSBs indicates a reference timing of the base station that isused to identify the set of resources, and perform an LBT procedure forinitiating the set of RMSI control channel transmissions. Thecommunications manager 1115 may be an example of aspects of thecommunications manager 1410 described herein.

The communications manager 1115, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 1115, or itssub-components may be executed by a general-purpose processor, a DSP, anASIC, a FPGA or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

The communications manager 1115, or its sub-components, may bephysically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, thecommunications manager 1115, or its sub-components, may be a separateand distinct component in accordance with aspects of the presentdisclosure. In some examples, the communications manager 1115, or itssub-components, may be combined with one or more other hardwarecomponents, including but not limited to an input/output (I/O)component, a transceiver, a network server, another computing device,one or more other components described in the present disclosure, or acombination thereof in accordance with aspects of the presentdisclosure.

The transmitter 1120 may transmit signals generated by other componentsof the device 1105. In some examples, the transmitter 1120 may becollocated with a receiver 1110 in a transceiver module. For example,the transmitter 1120 may be an example of aspects of the transceiver1420 described with reference to FIG. 14. The transmitter 1120 mayutilize a single antenna or a set of antennas.

FIG. 12 shows a block diagram 1200 of a device 1205 that supportsstaggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure. Thedevice 1205 may be an example of aspects of a device 1105, or a basestation 105 as described herein. The device 1205 may include a receiver1210, a communications manager 1215, and a transmitter 1240. The device1205 may also include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 1210 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to staggeredSSBs in frequency sub-bands for beamformed wireless communications,etc.). Information may be passed on to other components of the device1205. The receiver 1210 may be an example of aspects of the transceiver1420 described with reference to FIG. 14. The receiver 1210 may utilizea single antenna or a set of antennas.

The communications manager 1215 may be an example of aspects of thecommunications manager 1115 as described herein. The communicationsmanager 1215 may include a sub-band identification component 1220, anRMSI manager 1225, an SSB manager 1230, and an LBT manager 1235. Thecommunications manager 1215 may be an example of aspects of thecommunications manager 1410 described herein.

The sub-band identification component 1220 may identify a set offrequency sub-bands for transmitting a set of SSBs via a set oftransmission beams in an SSB beam sweeping procedure.

The RMSI manager 1225 may identify a set of resources for transmitting aset of RMSI control channel transmissions via the set of transmissionbeams in an RMSI beam sweeping procedure, where the set of resourcesspans two or more of the set of frequency sub-bands and transmit,responsive to completing the LBT procedure, the set of RMSI controlchannel transmissions via the set of transmission beams in the RMSI beamsweeping procedure using the set of resources.

The SSB manager 1230 may transmit the set of SSBs via the set oftransmission beams in the SSB beam sweeping procedure in each of the setof sub-bands, where the SSB beam sweeping procedure is performedseparately during non-overlapping time periods for each frequencysub-band of the set of frequency sub-bands, and where each of the set ofSSBs indicates a reference timing of the base station that is used toidentify the set of resources.

The LBT manager 1235 may perform an LBT procedure for initiating the setof RMSI control channel transmissions.

In some implementations, the actions performed by the sub-bandidentification component 1220, the RMSI manager 1225, the SSB manager1230, and the LBT manager 1235, as described herein, may facilitate theprocessor 1440, as described with reference to FIG. 14, to moreefficiently cause the device 1205 to perform various functions. Forexample, the device 1205 may transmit SSBs to a receiving device (e.g.,a UE) in a first beam sweeping procedure using a single frequencysub-band (e.g., selected by the device 1205 based on a long terminterference metric), which may facilitate relatively increased PSD ofthe SSB transmissions and accordingly may relatively improve thelikelihood that the receiving device successfully detects the SSBs. Thedevice 1205 may transmit control channel transmissions (e.g., RMSI PDCCHtransmissions) in a second beam sweeping procedure spanning additionalfrequency sub-bands and thus carrying additional information relative tothe SSB transmissions.

As such, the device 1205 may facilitate the receiving device to identifycertain beamforming characteristics for the second beam sweepingprocedure based on the SSBs transmitted by the device 1205 in the firstbeam sweeping procedure, and thus transmission beams of the second beamsweeping procedure may have reduced PSD relative to the first beamsweeping procedure while providing sufficient reliability for detectionby the receiving device. In using these beamformed communicationstechniques, the device 1205 may communicate with the receiving device(e.g., one of several UEs with which the device 1205 may communicate)with relatively greater efficiency and reliability, which maycorrespondingly reduce repeated transmissions and conserve frequency,time, and/or spatial resources. Accordingly, the device 1205 may reducea number of processing operations at the processor and other componentsof the device 1205, which may in turn provide power savings and conserveprocessing resources for the processor of the device 1205.

The transmitter 1240 may transmit signals generated by other componentsof the device 1205. In some examples, the transmitter 1240 may becollocated with a receiver 1210 in a transceiver module. For example,the transmitter 1240 may be an example of aspects of the transceiver1420 described with reference to FIG. 14. The transmitter 1240 mayutilize a single antenna or a set of antennas.

FIG. 13 shows a block diagram 1300 of a communications manager 1305 thatsupports staggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure. Thecommunications manager 1305 may be an example of aspects of acommunications manager 1115, a communications manager 1215, or acommunications manager 1410 described herein. The communications manager1305 may include a sub-band identification component 1310, an RMSImanager 1315, an SSB manager 1320, an LBT manager 1325, an SSB timingcomponent 1330, and an RMSI timing component 1335. Each of these modulesmay communicate, directly or indirectly, with one another (e.g., via oneor more buses).

The sub-band identification component 1310 may identify a set offrequency sub-bands for transmitting a set of SSBs via a set oftransmission beams in an SSB beam sweeping procedure.

The RMSI manager 1315 may identify a set of resources for transmitting aset of RMSI control channel transmissions via the set of transmissionbeams in an RMSI beam sweeping procedure, where the set of resourcesspans two or more of the set of frequency sub-bands. In some examples,the RMSI manager 1315 may transmit, responsive to completing the LBTprocedure, the set of RMSI control channel transmissions via the set oftransmission beams in the RMSI beam sweeping procedure using the set ofresources.

The SSB manager 1320 may transmit the set of SSBs via the set oftransmission beams in the SSB beam sweeping procedure in each of the setof sub-bands, where the SSB beam sweeping procedure is performedseparately during non-overlapping time periods for each frequencysub-band of the set of frequency sub-bands, and where each of the set ofSSBs indicates a reference timing of the base station that is used toidentify the set of resources. In some examples, the SSB manager 1320may identify an SSB time window for each of the set of frequencysub-bands for transmitting the set of SSBs. In some cases, each of theSSBs are transmitted according to a fixed time periodicity withoutperforming an LBT procedure.

In some cases, a same initial transmission beam of the SSB beam sweepingprocedure is used irrespective of when the SSB beam sweeping procedurestarts within the SSB time window. In some cases, each of the set ofSSBs has an associated SSB index that indicates a position of the SSBwithin a predetermined SSB pattern relative to a frame boundary withineach frequency sub-band of the set of frequency sub-bands.

In some cases, each of the SSBs transmitted via each of the set offrequency sub-bands indicates a same set of resources for the RMSIcontrol channel transmissions. In some cases, an SSB payload of each ofthe SSBs indicates the reference timing of the base station relative tothe respective SSB. In some cases, each of the set of SSBs provides anindication of a frequency offset of the set of resources relative to arespective frequency sub-band of the set of frequency sub-bands used totransmit the SSB.

The LBT manager 1325 may perform an LBT procedure for initiating the setof RMSI control channel transmissions. In some examples, the LBT manager1325 may perform an LBT procedure during the SSB time window for each ofthe set of frequency sub-bands prior to transmitting the set of SSBs,where the set of SSBs are transmitted responsive to successfullycompleting the LBT procedure.

The SSB timing component 1330 may determine SSB timing information toprovide with the SSB transmissions. In some cases, each frequencysub-band of the set of frequency sub-bands has a corresponding timeoffset from the reference timing of the base station.

The RMSI timing component 1335 may determine RMSI timing information toprovide with the SSB transmissions. In some cases, the set of resourcesincludes a predetermined starting time resource for the RMSI controlchannel transmission relative to a reference sub-band of the set offrequency sub-bands. In some cases, the set of resources is associatedwith an RMSI time window during which the RMSI beam sweeping procedureis to be performed, and where a starting time of the RMSI beam sweepingprocedure within the RMSI time window is dependent upon a time ofcompletion of the LBT procedure for initiating the set of RMSI controlchannel transmissions. In some cases, a duration of the RMSI time windowis based on a duration of the LBT procedure and a number of LBT attemptsthat the base station is configured to perform before dropping the setof RMSI control channel transmissions.

FIG. 14 shows a diagram of a system 1400 including a device 1405 thatsupports staggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure. Thedevice 1405 may be an example of or include the components of device1105, device 1205, or a base station 105 as described herein. The device1405 may include components for bi-directional voice and datacommunications including components for transmitting and receivingcommunications, including a communications manager 1410, a networkcommunications manager 1415, a transceiver 1420, an antenna 1425, memory1430, a processor 1440, and an inter-station communications manager1445. These components may be in electronic communication via one ormore buses (e.g., bus 1450).

The communications manager 1410 may identify a set of frequencysub-bands for transmitting a set of SSBs via a set of transmission beamsin an SSB beam sweeping procedure, identify a set of resources fortransmitting a set of RMSI control channel transmissions via the set oftransmission beams in an RMSI beam sweeping procedure, where the set ofresources spans two or more of the set of frequency sub-bands, transmit,responsive to completing the LBT procedure, the set of RMSI controlchannel transmissions via the set of transmission beams in the RMSI beamsweeping procedure using the set of resources, transmit the set of SSBsvia the set of transmission beams in the SSB beam sweeping procedure ineach of the set of sub-bands, where the SSB beam sweeping procedure isperformed separately during non-overlapping time periods for eachfrequency sub-band of the set of frequency sub-bands, and where each ofthe set of SSBs indicates a reference timing of the base station that isused to identify the set of resources, and perform an LBT procedure forinitiating the set of RMSI control channel transmissions.

The network communications manager 1415 may manage communications withthe core network (e.g., via one or more wired backhaul links). Forexample, the network communications manager 1415 may manage the transferof data communications for client devices, such as one or more UEs 115.

The transceiver 1420 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 1420 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1420 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1425.However, in some cases the device may have more than one antenna 1425,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1430 may include RAM, ROM, or a combination thereof. Thememory 1430 may store computer-readable code 1435 including instructionsthat, when executed by a processor (e.g., the processor 1440) cause thedevice to perform various functions described herein. In some cases, thememory 1430 may contain, among other things, a BIOS which may controlbasic hardware or software operation such as the interaction withperipheral components or devices.

The processor 1440 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1440 may be configured to operate a memoryarray using a memory controller. In some cases, a memory controller maybe integrated into processor 1440. The processor 1440 may be configuredto execute computer-readable instructions stored in a memory (e.g., thememory 1430) to cause the device 1405 to perform various functions(e.g., functions or tasks supporting staggered SSBs in frequencysub-bands for beamformed wireless communications).

The inter-station communications manager 1445 may manage communicationswith other base station 105, and may include a controller or schedulerfor controlling communications with UEs 115 in cooperation with otherbase stations 105. For example, the inter-station communications manager1445 may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, the inter-station communications manager1445 may provide an X2 interface within an LTE/LTE-A wirelesscommunications network technology to provide communication between basestations 105.

The code 1435 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1435 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1435 may not be directly executable by theprocessor 1440 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 15 shows a flowchart illustrating a method 1500 that supportsstaggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure. Theoperations of method 1500 may be implemented by a UE 115 or itscomponents as described herein. For example, the operations of method1500 may be performed by a communications manager as described withreference to FIGS. 7 through 10. In some examples, a UE may execute aset of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 1505, the UE may monitor one or more of a set of frequency sub-bandsfor an SSB from a base station, where each of the set of frequencysub-bands carries a non-overlapping instance of the SSB. The operationsof 1505 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1505 may be performed by asub-band identification component as described with reference to FIGS. 7through 10.

At 1510, the UE may receive a first instance of the SSB via at least afirst frequency sub-band of the set of frequency sub-bands based on themonitoring. The operations of 1510 may be performed according to themethods described herein. In some examples, aspects of the operations of1510 may be performed by an SSB monitoring manager as described withreference to FIGS. 7 through 10.

At 1515, the UE may determine a reference timing of the base stationbased on one or more of information from the first instance of the SSBor a frequency location of the first frequency sub-band relative to areference frequency sub-band of the set of frequency sub-bands. Theoperations of 1515 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1515 may beperformed by an SSB timing component as described with reference toFIGS. 7 through 10.

At 1520, the UE may identify, based on the reference timing, a set ofresources for a control channel transmission from the base station,where the set of resources spans two or more of the set of frequencysub-bands. The operations of 1520 may be performed according to themethods described herein. In some examples, aspects of the operations of1520 may be performed by an RMSI monitoring manager as described withreference to FIGS. 7 through 10.

At 1525, the UE may receive the control channel transmission via the setof resources. The operations of 1525 may be performed according to themethods described herein. In some examples, aspects of the operations of1525 may be performed by an RMSI monitoring manager as described withreference to FIGS. 7 through 10.

FIG. 16 shows a flowchart illustrating a method 1600 that supportsstaggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure. Theoperations of method 1600 may be implemented by a UE 115 or itscomponents as described herein. For example, the operations of method1600 may be performed by a communications manager as described withreference to FIGS. 7 through 10. In some examples, a UE may execute aset of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 1605, the UE may monitor two or more of the set of frequencysub-bands for respective instances of the SSB. The operations of 1605may be performed according to the methods described herein. In someexamples, aspects of the operations of 1605 may be performed by an SSBmonitoring manager as described with reference to FIGS. 7 through 10.

At 1610, the UE may combine two or more instances of the SSB from themonitored two or more of the set of frequency sub-bands. The operationsof 1610 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1610 may be performed by anSSB monitoring manager as described with reference to FIGS. 7 through10.

At 1615, the UE may determine a reference timing of the base stationbased on one or more of information from the first instance of the SSBor a frequency location of the first frequency sub-band relative to areference frequency sub-band of the set of frequency sub-bands. Theoperations of 1615 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1615 may beperformed by an SSB timing component as described with reference toFIGS. 7 through 10.

At 1620, the UE may identify, based on the reference timing, a set ofresources for a control channel transmission from the base station,where the set of resources spans two or more of the set of frequencysub-bands. The operations of 1620 may be performed according to themethods described herein. In some examples, aspects of the operations of1620 may be performed by an RMSI monitoring manager as described withreference to FIGS. 7 through 10.

At 1625, the UE may receive the control channel transmission via the setof resources. The operations of 1625 may be performed according to themethods described herein. In some examples, aspects of the operations of1625 may be performed by an RMSI monitoring manager as described withreference to FIGS. 7 through 10.

FIG. 17 shows a flowchart illustrating a method 1700 that supportsstaggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure. Theoperations of method 1700 may be implemented by a UE 115 or itscomponents as described herein. For example, the operations of method1700 may be performed by a communications manager as described withreference to FIGS. 7 through 10. In some examples, a UE may execute aset of instructions to control the functional elements of the UE toperform the functions described below. Additionally or alternatively, aUE may perform aspects of the functions described below usingspecial-purpose hardware.

At 1705, the UE may monitor one or more of a set of frequency sub-bandsfor an SSB from a base station, where each of the set of frequencysub-bands carries a non-overlapping instance of the SSB. The operationsof 1705 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1705 may be performed by asub-band identification component as described with reference to FIGS. 7through 10.

At 1710, the UE may receive a first instance of the SSB via at least afirst frequency sub-band of the set of frequency sub-bands based on themonitoring. The operations of 1710 may be performed according to themethods described herein. In some examples, aspects of the operations of1710 may be performed by an SSB monitoring manager as described withreference to FIGS. 7 through 10.

At 1715, the UE may determine a reference timing of the base stationbased on one or more of information from the first instance of the SSBor a frequency location of the first frequency sub-band relative to areference frequency sub-band of the set of frequency sub-bands. Theoperations of 1715 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1715 may beperformed by an SSB timing component as described with reference toFIGS. 7 through 10.

At 1720, the UE may identify, based on the reference timing, a set ofresources for a control channel transmission from the base station,where the set of resources spans two or more of the set of frequencysub-bands. The operations of 1720 may be performed according to themethods described herein. In some examples, aspects of the operations of1720 may be performed by an RMSI monitoring manager as described withreference to FIGS. 7 through 10.

At 1725, the UE may receive the control channel transmission via the setof resources. The operations of 1725 may be performed according to themethods described herein. In some examples, aspects of the operations of1725 may be performed by an RMSI monitoring manager as described withreference to FIGS. 7 through 10.

At 1730, the UE may identify a fixed time periodicity for monitoring theone or more of the set of frequency sub-bands for the SSB from the basestation. The operations of 1730 may be performed according to themethods described herein. In some examples, aspects of the operations of1730 may be performed by an SSB timing component as described withreference to FIGS. 7 through 10.

FIG. 18 shows a flowchart illustrating a method 1800 that supportsstaggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure. Theoperations of method 1800 may be implemented by a base station 105 orits components as described herein. For example, the operations ofmethod 1800 may be performed by a communications manager as describedwith reference to FIGS. 11 through 14. In some examples, a base stationmay execute a set of instructions to control the functional elements ofthe base station to perform the functions described below. Additionallyor alternatively, a base station may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1805, the base station may identify a set of frequency sub-bands fortransmitting a set of SSBs via a set of transmission beams in an SSBbeam sweeping procedure. The operations of 1805 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1805 may be performed by a sub-band identificationcomponent as described with reference to FIGS. 11 through 14.

At 1810, the base station may identify a set of resources fortransmitting a set of RMSI control channel transmissions via the set oftransmission beams in an RMSI beam sweeping procedure, where the set ofresources spans two or more of the set of frequency sub-bands. Theoperations of 1810 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1810 may beperformed by an RMSI manager as described with reference to FIGS. 11through 14.

At 1815, the base station may transmit the set of SSBs via the set oftransmission beams in the SSB beam sweeping procedure in each of the setof sub-bands, where the SSB beam sweeping procedure is performedseparately during non-overlapping time periods for each frequencysub-band of the set of frequency sub-bands, and where each of the set ofSSBs indicates a reference timing of the base station that is used toidentify the set of resources. The operations of 1815 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1815 may be performed by an SSB manager as describedwith reference to FIGS. 11 through 14.

At 1820, the base station may perform an LBT procedure for initiatingthe set of RMSI control channel transmissions. The operations of 1820may be performed according to the methods described herein. In someexamples, aspects of the operations of 1820 may be performed by an LBTmanager as described with reference to FIGS. 11 through 14.

At 1825, the base station may transmit, responsive to completing the LBTprocedure, the set of RMSI control channel transmissions via the set oftransmission beams in the RMSI beam sweeping procedure using the set ofresources. The operations of 1825 may be performed according to themethods described herein. In some examples, aspects of the operations of1825 may be performed by an RMSI manager as described with reference toFIGS. 11 through 14.

FIG. 19 shows a flowchart illustrating a method 1900 that supportsstaggered SSBs in frequency sub-bands for beamformed wirelesscommunications in accordance with aspects of the present disclosure. Theoperations of method 1900 may be implemented by a base station 105 orits components as described herein. For example, the operations ofmethod 1900 may be performed by a communications manager as describedwith reference to FIGS. 11 through 14. In some examples, a base stationmay execute a set of instructions to control the functional elements ofthe base station to perform the functions described below. Additionallyor alternatively, a base station may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1905, the base station may identify a set of frequency sub-bands fortransmitting a set of SSBs via a set of transmission beams in an SSBbeam sweeping procedure. The operations of 1905 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1905 may be performed by a sub-band identificationcomponent as described with reference to FIGS. 11 through 14.

At 1910, the base station may identify an SSB time window for each ofthe set of frequency sub-bands for transmitting the set of SSBs. Theoperations of 1910 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1910 may beperformed by an SSB manager as described with reference to FIGS. 11through 14.

At 1915, the base station may identify a set of resources fortransmitting a set of RMSI control channel transmissions via the set oftransmission beams in an RMSI beam sweeping procedure, where the set ofresources spans two or more of the set of frequency sub-bands. Theoperations of 1915 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1915 may beperformed by an RMSI manager as described with reference to FIGS. 11through 14.

At 1920, the base station may perform an LBT procedure during the SSBtime window for each of the set of frequency sub-bands prior totransmitting the set of SSBs, where the set of SSBs are transmittedresponsive to successfully completing the LBT procedure. The operationsof 1920 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1920 may be performed by anLBT manager as described with reference to FIGS. 11 through 14.

At 1925, the base station may transmit the set of SSBs via the set oftransmission beams in the SSB beam sweeping procedure in each of the setof sub-bands, where the SSB beam sweeping procedure is performedseparately during non-overlapping time periods for each frequencysub-band of the set of frequency sub-bands, and where each of the set ofSSBs indicates a reference timing of the base station that is used toidentify the set of resources. The operations of 1925 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1925 may be performed by an SSB manager as describedwith reference to FIGS. 11 through 14.

At 1930, the base station may perform an LBT procedure for initiatingthe set of RMSI control channel transmissions. The operations of 1930may be performed according to the methods described herein. In someexamples, aspects of the operations of 1930 may be performed by an LBTmanager as described with reference to FIGS. 11 through 14.

At 1935, the base station may transmit, responsive to completing the LBTprocedure, the set of RMSI control channel transmissions via the set oftransmission beams in the RMSI beam sweeping procedure using the set ofresources. The operations of 1935 may be performed according to themethods described herein. In some examples, aspects of the operations of1935 may be performed by an RMSI manager as described with reference toFIGS. 11 through 14.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as code division multiple access (CDMA),time division multiple access (TDMA), frequency division multiple access(FDMA), orthogonal frequency division multiple access (OFDMA), singlecarrier frequency division multiple access (SC-FDMA), and other systems.A CDMA system may implement a radio technology such as CDMA2000,Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000,IS-95, and IS-856 standards. IS-2000 Releases may be commonly referredto as CDMA2000 1×, 1×, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), E-UTRA, Institute of Electrical and ElectronicsEngineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20,Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications System (UMTS). LTE, LTE-A, and LTE-A Pro are releasesof UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, LTE-A Pro, NR,and GSM are described in documents from the organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned herein as well as other systemsand radio technologies. While aspects of an LTE, LTE-A, LTE-A Pro, or NRsystem may be described for purposes of example, and LTE, LTE-A, LTE-APro, or NR terminology may be used in much of the description, thetechniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro,or NR applications.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell maybe associated with a lower-powered base station, as compared with amacro cell, and a small cell may operate in the same or different (e.g.,licensed, unlicensed, etc.) frequency bands as macro cells. Small cellsmay include pico cells, femto cells, and micro cells according tovarious examples. A pico cell, for example, may cover a small geographicarea and may allow unrestricted access by UEs with service subscriptionswith the network provider. A femto cell may also cover a smallgeographic area (e.g., a home) and may provide restricted access by UEshaving an association with the femto cell (e.g., UEs in a closedsubscriber group (CSG), UEs for users in the home, and the like). An eNBfor a macro cell may be referred to as a macro eNB. An eNB for a smallcell may be referred to as a small cell eNB, a pico eNB, a femto eNB, ora home eNB. An eNB may support one or multiple (e.g., two, three, four,and the like) cells, and may also support communications using one ormultiple component carriers.

The wireless communications systems described herein may supportsynchronous or asynchronous operation. For synchronous operation, thebase stations may have similar frame timing, and transmissions fromdifferent base stations may be approximately aligned in time. Forasynchronous operation, the base stations may have different frametiming, and transmissions from different base stations may not bealigned in time. The techniques described herein may be used for eithersynchronous or asynchronous operations.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA, or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices(e.g., a combination of a DSP and a microprocessor, multiplemicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude RAM, ROM, electrically erasable programmable ROM (EEPROM), flashmemory, compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that can be used to carry or store desired programcode means in the form of instructions or data structures and that canbe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include CD, laser disc, optical disc, digital versatile disc (DVD),floppy disk and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an exemplary step that is described as “based on conditionA” may be based on both a condition A and a condition B withoutdeparting from the scope of the present disclosure. In other words, asused herein, the phrase “based on” shall be construed in the same manneras the phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method for wireless communications at a basestation, comprising: identifying a plurality of frequency sub-bands fortransmitting a plurality of synchronization signal blocks (SSBs) via aplurality of transmission beams; identifying a set of resources fortransmitting a plurality of remaining minimum system information (RMSI)control channel transmissions via the plurality of transmission beams,wherein the set of resources spans two or more of the plurality offrequency sub-bands; transmitting the plurality of SSBs via theplurality of transmission beams in each of the plurality of sub-bandsduring non-overlapping time periods for each frequency sub-band of theplurality of frequency sub-bands, and wherein each of the plurality ofSSBs indicates a reference timing of the base station that is used toidentify the set of resources; performing a listen-before-talk (LBT)procedure for initiating the plurality of RMSI control channeltransmissions; and transmitting, responsive to completing the LBTprocedure, the plurality of RMSI control channel transmissions via theplurality of transmission beams using the set of resources.
 2. Anapparatus for wireless communications at a base station, comprising: aprocessor, memory in electronic communication with the processor; andinstructions stored in the memory, wherein the instructions areexecutable by the processor to: identify a plurality of frequencysub-bands for transmitting a plurality of synchronization signal blocks(SSBs) via a plurality of transmission beams; identify a set ofresources for transmitting a plurality of remaining minimum systeminformation (RMSI) control channel transmissions via the plurality oftransmission beams, wherein the set of resources spans two or more ofthe plurality of frequency sub-bands; transmit the plurality of SSBs viathe plurality of transmission beams in each of the plurality ofsub-bands during non-overlapping time periods for each frequencysub-band of the plurality of frequency sub-bands, and wherein each ofthe plurality of SSBs indicates a reference timing of the base stationthat is used to identify the set of resources; perform alisten-before-talk (LBT) procedure for initiating the plurality of RMSIcontrol channel transmissions; and transmit, responsive to completingthe LBT procedure, the plurality of RMSI control channel transmissionsvia the plurality of transmission beams using the set of resources.